The problem is, if I hit the Tab key twice in quick succession, it will pop me out of the bad field
I can't replicate this behavior. It properly forces me back into the field with the errant entry, just as if I hit tab once. I am using Tk version 804.03 on: 
perl -v

This is perl 5, version 12, subversion 2 (v5.12.2) built for x86_64-li
+nux

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In reply to Re: Tk::Entry and double-Tab key weirdness by toolic
in thread Tk::Entry and double-Tab key weirdness by atreyu

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