If your mother in law is hand raking 4 acres of lawn, it would seem there would be no time to argue, why do want to change that again?😁
Seriously I have about 2 acres to mow and the ground is always damp so it grows fast. In my situation I cut more often so clipping don’t accumulate. When I do miss my shot and the grass gets long enough that I need to rake, I tow the lawn sweep while mowing, but that is limited success, to reduce back tracking I am thinking about rigging up a tow system to tow the sweeper off set so it picks up as the side discharge spits it out. Probably means more stop and dump time, so in reality for me the solution is back to square one, cut the grass often usually twice a week when it is really growing.