it's a waste of time 9/10 times. Best way to save time is to learn how to thoroughly read the passage, so well that you wont have to go back to it, unless you really have to. Sometimes I've spent 4.5 minutes on one passage and then I breezed through the questions in 3 minutes (and got all of them correct) because I read the passage properly. Focus on reading the passage in 4ish minutes and notice the organisation of the passage, the tone of the author, where the author's voice and opinion start etc.

Happened during mine too. Didn't make a difference