Only slightly less famous than "Never go up against a Silicilian when death is on the line"

Occasionally, I uncover phrases that I have been wrongly making solicisms out of for years. It wasn't until my freshman year of high school that I realized the phrase was not "for all intensive purposes" but "for all intents and purposes." Both of these make sense, except for the fact that an "intensive purpose" seems like something much more dire than I was using it as for all those years.

Apparently, I've been wrong about the phrase "to welch on a bet" for some years, as well. This was brought to my attention this morning in an article forwarded to me by my coworker regarding my postmodernist gurus at McSweeney's publishing. The article, Dave Eggers Desperate to Welsh on Bad Bet, caught me by suprise.

To Welsh on a bet? Really? How dare someone insult McSweeney's with a misspelling in the headline of the article! They shall know my fury! But, apparently, one doesn't "welch" on bets, but rather "Welshes" on them, as in, acts like a Welshman.

Thus: Never gamble with a Welshman, which is certainly less famous than "Never get involved in a land war in Asia."

I did a little bit of poking about to discover the (clearly Brit-centric) origin of the phrase. Most sources point to a poem called "Taffy was a Welshman," wherein the line following that particular phrase is "Taffy was a theif." The parrallel structure of those to lines is clearly intended to construct an identity of the Welsh people as theives. The folks in the WordWizard clubhouse further discuss it here. The WordWizard folks do go a little off-topic into other discussions of racist terms related to the Welsh people, but no one seems to take into account the change between the English spelling and the American spelling, which is why most Americans (and certainly myself) think that our version of the word is spelled "welch" rather than "Welsh."

I would assume that the "ch" character is intended to represent a voiced affricate, and the "sh" character is inteded to represent a voiceless affricate. My guess is that, in the importation of the phrase from British to American soil, the voice affricate slowly became voiceless over time.

My other theory is to blame Noah Webster, and guess that he changed the spelling of the phrase as part of his quest to reguarlize American orthography and differentiate it from British speech, further dividing British English from American English. Which would explain why the hatred and mistrust of Welshmen just simply doesn't translate to American soil, and why I believe the majority of us both write and say "to welch on a bet," rather than blaming those bloody, no good Welshmen.