That's actually the biggest reason that I never use titebond 3. It is extremely heat sensitive. It never really dries hard, but stays somewhat flexible, and even in hot summer days, the heat and humidity is enough that it can cause separations. That's why I went to resorcinol. Never had a problem since - I haven't tried heat treating a resorcinol bow, but the glue is intended for industrial strength applications, so I can't help but think that it would fare better.