> But why should idioms be sacrosanct?   Slang isn't.
 
Idioms aren't sacrosanct; they're conventional. A (hard to delimit!)
speech community recognizes 'if it ain't broke, don't fix it' as -- well,
not really an idiom, but a collocation (idioms usually don't relay their
literal meanings, as this does, if 'broke' is taken to apply in abstract
as well as concrete domains). Messing with a very familiar collocation or
idiom will rob it of its impact. If that is the impact you desire (and
right now, this expression has strong impact value in America), you don't
want to mess with it, in spite of what your grammar checker thinks. 'If
it isn't broke, don't fix it' sounds washed-out to me, and the gramamr
checker should also have flagged 'broke'. 'If it isn't broken, don't fix
it.' Blah! (My subjective view.)
 
Johanna
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Johanna Rubba   Assistant Professor, Linguistics              ~
English Department, California Polytechnic State University   ~
San Luis Obispo, CA 93407                                     ~
Tel. (805)-756-2184  E-mail: [log in to unmask]      ~
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