Jimbo,
Not a bad idea! The curious thing is most transfer bar breakage seems to be on new guns with few rounds fired. Indicating to me, it's a bad cast part.
Also if the pinch is severe enough for cumulative damage to the bar until it breaks, the trigger usually does not return properly or returns slower than normal, at least with lightened trigger return spring.
In 44 years of shooting new models, I've never had breakage. We hear about the ones that break here on the forum, but I don't think it's as prevalent as one might be convinced from reading the forum.
But hey, it's so simple to check, why not check, like you say? Good suggestion. Thx.