Just coming back here to say that we walked the Ruby Crest Trail from August 10-13. This is a really nice route-- very pretty and it was quite relaxing to not deal with issues such as scrambling, route finding, bears, or water problems.
All of the water sources mentioned in the Mike White book were running, it was surprisingly wet for mid-August after a not-huge snow year. There are still some patches of snow clinging to high nooks. Also, there were very few mosquitoes, really nice conditions all-around.
Our only day of unsettled weather (August 12) was on the day when we needed to do the long, exposed middle section between Overland Lake and Furlong Junction. This ended up being fine, we got started early and moved fast, and we found shelter to wait out a few passing storms. There wasn't any lightning. The wind and cooler temps made this day very pleasant.
We didn't see any people for the first 1.5 days, but then there were two other groups at Overland Lake. We saw a pair of trail runners and a pair of hunters on the way from Overland Lake to Furlong Junction. Then nobody until the downhill side of Liberty Pass. A gentleman we chatted with for a minute on the way down from Liberty Pass mentioned to us that Wines peak is named after his grandfather!! So overall, while this area is popular, it still feels pretty open and wild.
We had a big herd of sheep nearby while camping above Harrison Pass before starting this route, plus some cows. South Fork Smith Creek (which some reports say has lots of livestock) happened to be empty when we were there, but there was a lot of horse manure scattered around the obvious campsites. Then we passed another herd of sheep in North Fork Smith Creek. There was a solitary cow right at Overland Lake.
Going back to my original question "is mid-August too hot for the RCT" we were definitely happy to start walking 3 miles above Harrison Pass (instead of walking this section of 4WD road) and we were definitely happy to get an early start on the first two days of the trip. It never felt hot but we certainly did plenty of sweating. On the first two days the high in Elko was in the mid 90s. Temps were decently cooler on the second two days of the trip, I guess some sort of front passed through on the 12th. The 4WD road up from Harrison Pass has a couple of legit sections, it's not for Subarus.