... Finger joints gave Taylor grief with some guitar's joints coming loose so they switched to scarf joints. ...
May I ask from where you derived this info? I have personally
never heard that "joints coming loose" were the impetus for Taylor changing their joint. I do specifically recall, however, that Bob himself mentioned that they moved to the scarf joint for aesthetic reasons. Sure, folks said it, emailed it, wrote it in, and in 2007 they phased in the scarf joint. The perception that the finger joint is "cheap" or "weak" is exactly that: perception. But guitars being a "discretionary" purchase as opposed t,o say, food or mortgage payments, Taylor likely said (my guess here), sure, let's change the joint since folks don't feel good about a guitar with joint x, so let's go with joint y. Economic/business decision, methinks; but not one based on structural failure.
OTOH, I do recall Taylor having stated that they had some "glue issues" and necks way back when ...these were very limited in number, and seemed to fall on the BabyT. At least to my aging recollection
Edward