Although Bill makes sensible suggestions (belt and suspenders), I don't predict the second calamity happening with a Nitto M12.
The lower mounts of the M12 end in thick horizontal plates that slide over your brake post (not likely to pivot) and the upper mount of the M12 is a solid steel bolt that goes into the brake hole on your fork (not very fragile).
I really like the M12, and I feel that it should be more sturdy and load-capable than the other Nitto mini front racks, since it has no moveable parts. However, I've never loaded my M12 very heavily nor mounted a basket. So far, mine has only held a Small Trunksack with a load of tools and sundries. And I have heard of M12 failures on other forums, but I've never seen one to determine how/where the rack broke.
Back to the thread topic (baskets on mini racks), I had a Mark's rack / small Wald basket combo on my Rivendell Road/650b (along with moustache bars), and I definitely overloaded it a couple times. I carried several beers (12 glass bottles, 16 pint cans) and also overloaded it with camping stuff. The basket never bent and the Mark's rack was secure. But, I didn't like how the bike handled with a loaded basket (wheel flop).
Also, I didn't like the moustache bars for long touring days (can't get low/forward out of the wind). I actually traded the moustache bars, dirt drop stem, and brake levers toward a rando bag from David Banzer (Treetop designs).
Now, I have that Treetop rando bag on my Mark's rack (with long stays to the dropout eyelets), and the handling is a bit better. There is still noticeable wheel flop, but I think this setup is more secure. Running the stays to the dropouts removed any side sway from the p-clamps, and the rando bag is attached in three places (VO decaleur, tombstone strap, and bottom strap).
Plus, the rando bag is very easy to use. Now I know why that design is so favored by brevet riders.
Eventually, I'd like to try the rando bag on a low trail fork, but I haven't yet.
Cheers,
Tim