Looks like it's going to spawn a tight discussion about what gameplay features automatically make this run faster. It's just before, we only were speaking about dialogs or mid-room lag on that matter, since it's the cheapest way and must not be accounted as an improvement. Now, the run kind of deliberately picks the easier version and benefits by time. But does it match the tech level of the current movie? I mean, since the latter uses the harder difficulty, it showcases more tech value unless it misses some improvement possible in the U version.
I was in somewhat similar situation with this movie:
[1930] NES Zen: Intergalactic Ninja by feos in 11:34.21
The previous one used the medium difficulty, and if I switched to hard, my improvements would become uncountable, due to losses in different places. So I picked the same difficulty to know for sure what I improved and what I didn't improve.
However, this run was accepted as a tech and entertainment improvement over the predecessor:
[945] Genesis Gunstar Heroes "2 players" by arkiandruski in 35:28.92
despite of being slower in real time for using the hardest difficulty.