dont be naive. if they do that then players will suddenly get something in their eye, or have equipment problems and just call for time so they video gets it looked at. the stop in play in inherent to the rule. there is no way to have one without the other. it's already better than hockey where a team in Toronto has to look at every goal and lots of other plays that the refs are to afraid to call. those take forever. letting the teams figure out in 15-20 seconds that they shouldn't challenge takes less time than one 5 minute fight
besides. as long as it's less than 10 times a game, it's still losing less time than one temper tantrum that is followed by an ejection and then a hissy fit for getting ejected. this is saving time even if you dont feel it is.