This is my first and may also be my last post here :)
I came here after watching a speedrun history of Contra and took me back when I used to play it when i was a child. But one thing struck me during the video, is that noone attempted to just jump over the tank in Snowfield, skipping it entirely. I used to do that all the time and I didn't even know what speedrun was but i used to manage jumping over the tank while it was entering the scene (if i remember correctly). Don't know how much time is saved though as it was such a long time ago i cannot remember.
However I owned a bootleg NES and not an original, so I'm not sure if it can be done in an original system and copy of Contra.
Anyway, thanks for reading, sorry if this has been already posted and is known.