This is a step in the direction of continuously polling the queue fd on the server side, removing the need for ntsync to notify wineserver before / after waiting on the queue.
Do you have performance data that shows an improvement in applications?
I don't know if this makes the code simpler or better in other ways—great if so—but if not, and there's no instance where avoiding that server call is known to be a bottleneck, I wouldn't be inclined to do it personally.
In any case I hope this isn't going to be considered necessary for ntsync to be upstreamed.