I did come up with this, but I'm not sure if it is the best way, since the bind is not in the sub bindRdOnly{}, and may have some unforseen impact on Control Bindings.

#!/usr/bin/perl
use warnings;
use strict;
use Tk;

package Tk::MyText;

require Tk::Text;
use base qw/Tk::Text/;
Construct Tk::Widget 'MyText';

sub ClassInit {
  my($class,$mw) = @_;
  $class->SUPER::ClassInit($mw);
  $mw->bind($class,'<Control-KeyPress>','NoOp');
  $class;
}
##################################################### 

package main;

my $top = tkinit;
my $text = $top->MyText->pack;

$text->bind('<Control-g>',
  sub {$text->insert('end',"<-How do I supress this?\n")
     });

MainLoop;
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