When i look at that chart i see a reflection of exactly how i'm seeing those players used. It's clear as day watching who's being used to check and score and the chart reflects that. I didn't even bother to look up player usage before my initial comment today yet lo and behold when i did the chart reflected exactly what i'm seeing, that suggests to me that relCorsi is very effective in displaying true QoC. Tippett is a very intentional coach.
But it's a fair point still and perhaps comparing the two charts might be even more beneficial. Here's one that i believe is using raw corsi.
Edmonton Oilers Player Usage Chart | leftwinglock.com
I'd suggest this one looks less accurate by my eye but still relevant. Perhaps the truth is in the middle? It's tough because stats are far from perfect evaluators given their limitations in providing context. I'd imagine if you asked Tippett how he's using them he'd tell you they're a checking line, hence he often starts them against other teams top lines to begin the game.