Does the timer need to be visible during the recording or can a timer be edited in afterwards?

Im interested in trying out a overcooked speedrun, but it doesn't seem like the category is very active. Can anyone help me with understanding in what areas you can actually save time and which areas are basically just auto scrollers, this would be really useful so I can know what areas to actually look at for a speedrun instead of watching the whole thing and trying to figure it out myself