I'm not sure if anyone's posted results with it off, but there has been a fairly lengthy discussion in the AQL thread trying to get a good balance between speed and latency/trying to track down throughput bugs. (Although the user is testing with a mt7621+7615, not mt7622+7915.)
The thread is AQL in general, despite ath10k in the title. 
One should probably take into account that it looks like mediatek were trying to pass cert, thus they may have just disabled it in order for a test suite to pass/complete. It's nice to see them openly developing on top of mt76 though.