On the route I'm looking at for Sept. (after labor day), fares actually seem to be higher than non-sale fares. Under the fly and stay fare sale banner, CVG-YYZ via ORD was up at $550. Record low I've paid is about $270, with normal fares anywhere ~$350-$550. Is giving me a W on CVG-ORD/return seg's, and S on ORD-YYZ and return segs. Funny though, to BUF on same dates is only $218, but is giving me S fares on all segments, even on the same first and last segments CVG-ORD and vice-versa. Not sure why it won't pull S up for everything.
But then again, I almost forgot that I've vowed to stop trying to figure out how UA or any other airline prices, and why they often have "sales" that seem to pull up fares taht are at normal or higher, even when checking several dates/flights that meet the criteria.