Looks to me as if OP may be talking about the benefits of aeration during fermentation, rather than agitation for the sake of resuspending the yeast. And there may be some merit to aeration beginning after the onset of active fermentation. If agitation is your method of aeration and it's also causing the brunhefe to dissolve into the beer, that's obviously not good.
As to continuing aeration after the onset of fermentation, quoting from "Making Big Brews Like the Pros", by Amahl Scheppach in the current issue of Zymurgy, in the section on aeration: "Aerate early, heavily and often...You can really help your "super" beers by repeating aeration or oxgenation during the lag phase and on into actual fermentation. This isn't something that the pros gerenarally do, but theoretically intermittent aeration can be done as late as five days into fermentation. How intermittent? As often as every four to six hours, if you can manage it."
I've read many times suggestions that big beers be given a shot of oxygen 12-18 hours into fermentation to boost reproduction.
OP, are you suggesting that there may be benefit from aeration, or swirling the yeast back into suspension?