I'd say that kind of "anecdotes" are sometimes exactly what certain people are after, because the obvious common-sense version of this is "change it, don't ride it!". I guess there wouldn't be any topic at all if it was down to that and I think what he really wants to know what other people's experiences with cracked rims are. So this is why, in my point of view, those "anecdotes" are valuable: because they bring some down-to-earthness to an issue that otherwise relies only on manufacturer suggestions.
Is it really so bad to find out that Mavics are actually built from a quality alloy that can live with cracks to some point? I thought we should share thoughts that help fellow Retrobike users... Maybe it's helpful to someone who cracked a rim and just wants to get home or to someone who has a cracked rim on a bike that is ridden lightly and has to wait one more week for a new one. So I think in this case it is obvious what the first response should be (don't ride it!) and that the one who chooses to ignore it is on his own responsibility.
As for other anecdotes (and certainly not myths), I could go on and tell you how the same guy rode a longitudinally cracked DeeMax to two National Downhill Championships, but you'll just say that my reminiscing is dangerous to other people who might jump the cracked rim bandwagon. Ooops!
And if isn't clear, I'll just say it openly: those who live in parts of the world where a good bikeshop is around the corner are lucky but sometimes take things for granted. I couldn't be more grateful for being now able to go to one and just buy what I need. 12 years ago, getting a good fork or frame was a mission and obtaining quality parts was a quest. 1994 Alivio was smuggled beneath the counters in 1998 and I know people who were backpacking for 3 days to Hungary only to get some cranks and brakes! Parts that were broken or considered not worthy by others helped us out a lot. I can vividly recall how friends of mine dug in the dumpsters at Maribor to get their M950 XTR or how all broken SID uppers from the 1998 Budapest World Cup were recycled into lightish aluminum "upgrade" steerers and god knows what else... Of course, the World Cup used to be more generous with trash cans back in the day. Today it's mostly stuff that can't be used anymore, but in the meantime we don't need it.
I salute you!
Mx