diff --git a/src/fmelt.c b/src/fmelt.c
index ce342b106..953ae1886 100644
--- a/src/fmelt.c
+++ b/src/fmelt.c
@@ -63,7 +63,8 @@ SEXP whichwrapper(SEXP x, SEXP val) {
 
 static const char *concat(SEXP vec, SEXP idx) {
   if (!isString(vec)) error(_("concat: 'vec' must be a character vector"));
-  if (!isInteger(idx) || length(idx) < 0) error(_("concat: 'idx' must be an integer vector of length >= 0"));
+  if (!isInteger(idx))
+    error(_("concat: 'idx' must be an integer vector"));
 
   static char ans[1024];  // so only one call to concat() per calling warning/error
   int nidx=length(idx), nvec=length(vec);
@@ -802,7 +803,8 @@ SEXP fmelt(SEXP DT, SEXP id, SEXP measure, SEXP varfactor, SEXP valfactor, SEXP
   }
   int protecti=0;
   dtnames = PROTECT(getAttrib(DT, R_NamesSymbol)); protecti++;
-  if (isNull(dtnames)) error(_("names(data) is NULL. Please report to data.table-help"));
+  if (isNull(dtnames))
+    internal_error(__func__, "names(data) is NULL");
   if (LOGICAL(narmArg)[0] == TRUE) narm = TRUE;
   if (LOGICAL(verboseArg)[0] == TRUE) verbose = TRUE;
   struct processData data;
diff --git a/src/fread.c b/src/fread.c
index 59dfbd23e..746d38863 100644
--- a/src/fread.c
+++ b/src/fread.c
@@ -1888,11 +1888,14 @@ int freadMain(freadMainArgs _args) {
     // *2 to get a good spacing. We don't want overlaps resulting in double counting.
   }
   if (verbose) {
-    DTPRINT(_("  Number of sampling jump points = %d because "), nJumps);
-    if (nrowLimit<INT64_MAX) DTPRINT(_("nrow limit (%"PRIu64") supplied\n"), (uint64_t)nrowLimit);
-    else if (jump0size==0) DTPRINT(_("jump0size==0\n"));
-    else DTPRINT(_("(%"PRIu64" bytes from row 1 to eof) / (2 * %"PRIu64" jump0size) == %"PRIu64"\n"),
-                 (uint64_t)sz, (uint64_t)jump0size, (uint64_t)(sz/(2*jump0size)));
+    if (nrowLimit<INT64_MAX) {
+      DTPRINT(_("  Number of sampling jump points = %d because nrow limit (%"PRIu64") supplied\n"), nJumps, (uint64_t)nrowLimit);
+    } else if (jump0size==0) {
+      DTPRINT(_("  Number of sampling jump points = %d because jump0size==0\n"), nJumps);
+    } else {
+      DTPRINT(_("  Number of sampling jump points = %d because (%"PRIu64" bytes from row 1 to eof) / (2 * %"PRIu64" jump0size) == %"PRIu64"\n"),
+              nJumps, (uint64_t)sz, (uint64_t)jump0size, (uint64_t)(sz/(2*jump0size)));
+    }
   }
   nJumps++; // the extra sample at the very end (up to eof) is sampled and format checked but not jumped to when reading
   if (nrowLimit<INT64_MAX && nrowLimit>0) nJumps=1; // when nrows>0 supplied by user, no jumps (not even at the end) and single threaded
@@ -1930,8 +1933,10 @@ int freadMain(freadMainArgs _args) {
       }
       if ( (thisNcol<ncol && ncol>1 && !fill) ||
            (!eol(&ch) && ch!=eof) ) {
-        if (verbose) DTPRINT(_("  A line with too-%s fields (%d/%d) was found on line %d of sample jump %d. %s\n"),
-                             thisNcol<ncol ? _("few") : _("many"), thisNcol, ncol, jumpLine, jump, jump>0 ? _("Most likely this jump landed awkwardly so type bumps here will be skipped.") : "");
+        if (verbose)
+          DTPRINT(thisNcol<ncol ? _("  A line with too-few fields (%d/%d) was found on line %d of sample jump %d. %s\n")
+                                : _("  A line with too-many fields (%d/%d) was found on line %d of sample jump %d. %s\n"),
+                  thisNcol, ncol, jumpLine, jump, jump>0 ? _("Most likely this jump landed awkwardly so type bumps here will be skipped.") : "");
         bumped = false;
         if (jump==0) lastRowEnd=eof;  // to prevent the end from being tested; e.g. a short file with blank line within first 100 like test 976
         break;
@@ -2035,7 +2040,10 @@ int freadMain(freadMainArgs _args) {
     }
     if (verbose) {
       if (sampleLines==0) {
-        DTPRINT(_("  'header' determined to be %s because there are%s number fields in the first and only row\n"), args.header?"TRUE":"FALSE", args.header?_(" no"):"");
+        if (args.header)
+          DTPRINT(_("  'header' determined to be TRUE because there are no number fields in the first and only row\n"));
+        else
+          DTPRINT(_("  'header' determined to be FALSE because there are number fields in the first and only row\n"));
       } else {
         if (args.header)
           DTPRINT(_("  'header' determined to be true because all columns are type string and a better guess is not possible\n"));
@@ -2621,7 +2629,7 @@ int freadMain(freadMainArgs _args) {
 
   if (stopTeam) {
     if (internalErr[0]!='\0') {
-      STOP("%s %s: %s. %s", _("Internal error in"), __func__, internalErr, _("Please report to the data.table issues tracker"));  // # nocov
+      STOP(_("Internal error in %s: %s. Please report to the data.table issues tracker"), __func__, internalErr); // # nocov
     }
     stopTeam = false;
 
diff --git a/src/fsort.c b/src/fsort.c
index e03c4639b..5501cdbaa 100644
--- a/src/fsort.c
+++ b/src/fsort.c
@@ -98,6 +98,16 @@ int qsort_cmp(const void *a, const void *b) {
   return (x<y)-(x>y);   // largest first in a safe branchless way casting long to int
 }
 
+static size_t shrinkMSB(size_t MSBsize, uint64_t *msbCounts, int *order, Rboolean verbose) {
+  size_t oldMSBsize = MSBsize;
+  while (MSBsize>0 && msbCounts[order[MSBsize-1]] < 2)
+    MSBsize--;
+  if (verbose && oldMSBsize != MSBsize) {
+    Rprintf(_("Reduced MSBsize from %zu to %zu by excluding 0 and 1 counts\n"), oldMSBsize, MSBsize);
+  }
+  return MSBsize;
+}
+
 /*
   OpenMP is used here to find the range and distribution of data for efficient
     grouping and sorting.
@@ -252,12 +262,8 @@ SEXP fsort(SEXP x, SEXP verboseArg) {
 
     if (verbose) {
       Rprintf(_("Top 20 MSB counts: ")); for(int i=0; i<MIN(MSBsize,20); i++) Rprintf(_("%"PRId64" "), (int64_t)msbCounts[order[i]]); Rprintf(_("\n"));
-      Rprintf(_("Reduced MSBsize from %zu to "), MSBsize);
-    }
-    while (MSBsize>0 && msbCounts[order[MSBsize-1]] < 2) MSBsize--;
-    if (verbose) {
-      Rprintf(_("%zu by excluding 0 and 1 counts\n"), MSBsize);
     }
+    MSBsize = shrinkMSB(MSBsize, msbCounts, order, verbose);
 
     bool failed=false, alloc_fail=false, non_monotonic=false; // shared bools only ever assigned true; no need for atomic or critical assign
     t[6] = wallclock();
diff --git a/src/gsumm.c b/src/gsumm.c
index 7b6c12b59..c1f0fef81 100644
--- a/src/gsumm.c
+++ b/src/gsumm.c
@@ -221,7 +221,6 @@ void *gather(SEXP x, bool *anyNA)
 {
   double started=wallclock();
   const bool verbose = GetVerbose();
-  if (verbose) Rprintf(_("gather took ... "));
   switch (TYPEOF(x)) {
   case LGLSXP: case INTSXP: {
     const int *restrict thisx = INTEGER(x);
@@ -341,7 +340,7 @@ void *gather(SEXP x, bool *anyNA)
   default :
     error(_("gather implemented for INTSXP, REALSXP, and CPLXSXP but not '%s'"), type2char(TYPEOF(x)));   // # nocov
   }
-  if (verbose) { Rprintf(_("%.3fs\n"), wallclock()-started); }
+  if (verbose) { Rprintf(_("gather took %.3fs\n"), wallclock()-started); }
   return gx;
 }
 
diff --git a/src/init.c b/src/init.c
index 83917754a..18ad71ab8 100644
--- a/src/init.c
+++ b/src/init.c
@@ -222,9 +222,9 @@ void attribute_visible R_init_data_table(DllInfo *info)
   if (ld != 0.0) error(_("Checking memset(&ld, 0, sizeof(long double)); ld == (long double)0.0 %s"), msg);
 
   // Check unsigned cast used in fread.c. This isn't overflow/underflow, just cast.
-  if ((uint_fast8_t)('0'-'/') != 1) error(_("The ascii character '/' is not just before '0'"));
+  if ((uint_fast8_t)('0'-'/') != 1) error(_("Unlike the very common case, e.g. ASCII, the character '/' is not just before '0'."));
   if ((uint_fast8_t)('/'-'0') < 10) error(_("The C expression (uint_fast8_t)('/'-'0')<10 is true. Should be false."));
-  if ((uint_fast8_t)(':'-'9') != 1) error(_("The ascii character ':' is not just after '9'"));
+  if ((uint_fast8_t)(':'-'9') != 1) error(_("Unlike the very common case, e.g. ASCII, the character ':' is not just after '9'."));
   if ((uint_fast8_t)('9'-':') < 10) error(_("The C expression (uint_fast8_t)('9'-':')<10 is true. Should be false."));
 
   // Variables rather than #define for NA_INT64 to ensure correct usage; i.e. not casted
@@ -364,7 +364,7 @@ SEXP beforeR340(void) {
 extern int *_Last_updated;  // assign.c
 
 SEXP initLastUpdated(SEXP var) {
-  if (!isInteger(var) || LENGTH(var)!=1) error(_(".Last.value in namespace is not a length 1 integer"));
+  if (!isInteger(var) || LENGTH(var)!=1) error(_(".Last.updated in namespace is not a length 1 integer"));
   _Last_updated = INTEGER(var);
   return R_NilValue;
 }