as far as I remember getting 17 on agent with only the first door normally opened by guard being closed needed about as good a run as 16 just without the boost. so for sa/00 there's at least 1 more door that can be opened for sure, so if that's closed aswell, it easily adds up to a whole second lost, so imo there's no reason for those that get 56s with ALL doors closed not to get 55s. I'd even go as far as to say 55 should be reasonably cake and would take about 3 hours maybe. I'm just speculating from what you guys are saying, so if you're all not exaggerating then I'm not either.