I keep circling back to things Ryan Day said about Fields when he got to Ohio State which seem to have been confirmed at rookie camp to some degree. The talent was obvious, the work ethic matched, and Fields was sharp in the meeting room translating classroom to the field.
As a coach, you have to trust your eyes and not overthink it. If Fields continues to show command through OTAs and into camp, he's your guy. There'll be some ups and downs as he adjusts to the pro game. The only other factor here is whether the line is a hot mess.