So, someone explained quite well how FP impacts lines. The interesting things is that SE can only handle X number of rides. So, FP+ doesn't impact that capacity per se. However, in my opinion, the impact is on the line not moving consistently. You start moving and then FP groups come in. So, the line stalls (although, if you're the one with the FP you feel pretty happy). Then, the group passes through and then the line starts moving. So, SE's wait times are longer for stand-by to accommodate FP when, if the ride was off of FP, the line times would be a little shorter but would move. I don't know if Tiering is impacting it or not. Bear all this in mind that I do not like the FP+ process at all. I'd rather show up and wait in lines without the aggravation of FP.