The trouble with Possession WRs is that they have been, and perhaps will continue to be, the most effected by the changes in the SIM and other nerfs. My own guy's, and many others who I OCed, production would vary wildly from one season to another, despite staying on the same team. Maybe, as an OC I wasn't quick enough to react to the changes, but nuch of it seemed to be related to SAs, which would be poweful one season and then useless the next. I even tested this myself by removing certain AEQ pieces which had +6 of a Poss. WR SA and there was no noticeable change at all.
That's why I can understand why many Poss. WRs are simply slightly slower and better at catching/jumping than Speedster WRs. Because at least that way, you know you can expect a steady level of production.