As an old timer, when we hiked the PCT in '81 not everything was completed, including the trail through the Tehachapis and Walker Pass, so we had to walk down the Kelso road to Weldon, and then from there climb up into the Sierras. The road walk was a road walk, followed by another few miles north out of Weldon, but from there the temporary PCT was forested and well watered, with a nice high pass (Siretta) and very enjoyable. It sounds from the journals I’ve read that the PCT from Kelso Rd. to Rockhouse Basin (where the old PCT rejoins the route) is hot, waterless, unpleasant, and goes through a couple of burns (I don’t know whether the old route has been burned). As the old route is shorter, has better water, and takes you right through a resupply point (Weldon) I would certainly consider it, if in fact it is still viable. The trail north of Weldon was a long established USFS trail, followed by FS roads by big Sierra meadows and trout fishing.
Pappy