You claim that PFF doesn't account for "context" but if you read the article thoroughly, you'll find that they actually go out of their way to account for context in their analysis.
from the PFF article:
"A MORE DETAILED ANALYSIS
Ok, that was a lot of aggregating, and while pressure rate at the season level may be more on the quarterback than on the offensive line, what about at the play level? Many detractors of evidence-based analysis of football claim that “context” is the most important element of getting the analysis right. We don’t disagree, so we folded in contextual data like down, distance, yards to go, time left on the clock, dropback type, whether there was play action or an RPO, whether there was a blitz, as well as the time to throw on the play (if applicable). We also used our play-by-play participation data to map who was the left through right tackle on the play and used their aggregated pressure rate allowed through that season and the previous season, and that of the quarterback. To estimate the implied pressure rate of the offensive line as a whole, we simply took one minus the product of each player’s successful block rate, which is one minus their pressure rate allowed. We only used plays where each of the six players of interest had accumulated 100 or more passing snaps over the timeframe considered and did not consider the contribution of tight ends or running backs due to sample size."
I don't think they're the one with the blind spot.
