No glitches as far as I can see but he seems to be oblivious about the usage of different items. Maybe because he does not pay much attention to text or because it isn't so obvious for people who didn't play the game in the Alpha.
For example he gets confused about health shards and does almost never collect them. he thinks they recharge energy inside a room, so he skips them when he does not use his energy gun (which he does oten because he uses the Flame Tank).
This gave me the idea that you could probably add a real item that replenishs energy in a room, would also add to the variety of items you can find.
Hearteater said soemthing similiar in his thread
here.
While I disagree with most of his ideas, I like the idea that tehre are pickups that replenish energy for a room.