Who needs 5 minutes to determine an offside or a foul? Most of the times you can watch the replay twice in 20 seconds if the technology is up to date. Its not like players protesting decisions dont take up time
that's a naive assumption; things like these can happen and probably will happen if allowed :
1. the entire team, coaches andn team officials rushes to the match officials demanding video
2. they are all going to watch that video from the ipad at the bench (because not all stadium has large screen, so I assume ipad or laptop or something will be the official tool, and yes I'd assume that teams will demand to be able to watch the video themselves! and that is logical assumption, right, because why shouldn't "the defendant" and "the accused" be prohibited from seeing the evidence that are being used to judge them? you don't want to be convicted based on someone else's sole judgment over a video evidence, right?)
3. they are all going to argue to the ref and other match officials, before and after seeing the video
4. they are all going to stall whatever happen next, casually walking slowly to get back into the game if things are in their favor
why do you guys think it'll over be 20 seconds? this ain't fifa/pes lol.