I don’t see how this changes the problem where there is an expected guarantee of a rapid response except that now two people are expected to be available and would now need to directly coordinate in order to ensure one person’s going for a swim doesn’t interfere with the other’s WoW raid.
I guess to me that seems worse because that’d effectively double the number of off-hours accountability per teammate. Not only do you need to be first on call for your primary hours, therefore severely restricting the quality of your “free time” but now you ALSO have to be secondary on call for that irresponsible coworker that goes afk without properly communicating for 2 hours, dipping twice into your actual free time.
Out of 168 hours in a week, there are maybe up to 8 where I want to do something that interferes with being oncall. There's no downside real downside to being oncall for the other 160 hours. But I would get a lot of disutility from losing my freedom during those 8.
