Roasting Pork Butt at 215F
I usually cook Pork Butt (or Boston Butt) for around 20 to 25 mins per pound 

This link http://m.recipetips.com/kitchen-tips/t--907/pork-cooking-times.asp has a list of suggested cooking times.

I usually do my pork at around 160f to 180f. And would worry that cooking at such a high temperature would mean the meat would be over cooked on the outer parts before the inner part was cooked, meaning some of the meat might be quite tough.