Unfortunately, faculty don't feel competent in doing teaching scholarship. The process is important, but unless it can be shared a base of knowledge is never created. It would be unfortunate if a scholarship of teaching becomes entrenched in academia and falls prey to the worst of its models. TA should encourage classroom research. Lots of teaching takes place in private and nobody ever finds out about it.
Faculty are too busy to reflect much on a scholarship of teaching.
Use more conventional terms like teaching research or education research. We need more scholarship of learning. Maybe we would be shocked at how little impact a scholarship of teaching would have. Teaching is the one thing all disciplines have in common. If we are not committed to our students how can we expect them to be committed to us.