Never having used Perl 4, I'd be really interested to see half a dozen or so examples of P4 -v- P5 code to demonstrate your point. I've acquired a passing awareness of some of the differences through osmosis. Eg. Hashes and arrays couldn't be nested? Though why not escapes me, when the both contain scalars and refs are scalars. Unless there were no refs in P4?

I guess my point is that for the old hands who did several years of P4 before the last 10 (?) of P5, your "Stop writing P4" argument may be enough, but for all those (like me, and maybe 30%, 40%, 50% (more?) of current users), that only came on board since P5, it alludes to something that seems like it probably makes sense, but without examples of what we are doing to offend you, the allusion is only fleeting. It lives in "Yeah! Right on! Like, you mean like... um... er"-land