Yes, the front running SSB/SSC drivers ARE using the solo compound in qualifying.

Watch Harry Manning (SSB Champ)in qualifying sometime. He clicks off 2 or 3 hot laps, backs of for a few laps to cool the tires down, gets on it for 2-3 laps, backs off, etc.

I think Toby G. Ran the soft compound in Qual on his pole sitting Acura, but switched to the harder tire for the race, knowing it wouldn't last for the race.

I think they would make awsome tires on a damp/drying track.