I use walk-away splits to create brood breaks as part of varroa management.
The only real trick: Time the split to coincide with your local dearth. There are generally plenty of drones around still, to get your new queen mated, but a break in brood here (plus sugar dusting during the period without larvae, if you do that) not only helps reduce varroa load but also reduces the amount of stores used during the dearth.
Where I am, in NC, this means we do splits around June 20 or first week of July. Many experienced keepers in my county club have said this was crazy. But they said that about foundationless too... So far, we've had absolutely no trouble with hives getting built up for winter. This might not work as well for you if you don't have at least a small fall flow, but could be worth a shot.