How many times can you or have you heated the same piece of osage to get it to bend like you want before you say it is over cooked or heated?  Is there a point to where it does more harm than good?

I think I have heated em six or seven times, maybe more to get it just right. As long as you don't scorch the wood, is say you can heat em as many times a needed. Remember to let the stave rehydrate before you bend it.

I agree.  I have had them break when I bend them too soo after a serious adjustment.  I am pretty sure that was from overdrying but I don't really ahve any empirical evidence for that.  I generally give a well-heated bow at least a week before serious bending.  Minor adjustments at the tips or to correct a slight twist where I don't get the working areas real hot get a day if that.

I do it the same as John Charlie.

Heat it as many time as needed. Remember to use oil on the area to be heated.