I didn't see enough from that to convince me, there could be a handful of reasons why his chain was sticky at the end, and I won't take his word for it as fact without supporting facts. I will take into consideration that maybe it does oil less, but I can't see why. If the pump gives one (for example) pulse of oil per rotation of the chain, it is 1 pulse per rotation no matter the rpm. So, the chain always sees the same amount of oil for the same distance traveled. Distance traveled affects how much surface area the chain can transfer oil onto to loose the oil. If the oiler is properly set to keep the chain lubed for the length of bar it has to travel, then it shouldn't see any less oil even at slower speeds.
I also have a timer to confirm a faster cut at slower rpm. I've tried chains of varying practical aggressiveness, and it always cuts faster in that type of wood at a slower chain speed. Most of the chains I've tested are too aggressive to bore cut with. Even when milling that same Ash, it would lock in to this slow rpm where the saw would barely run, but was cutting much faster in the process. I'd be aiming for high rpm in the cut if I was testing saws in soft wood.