I must be misreading you saying it's conceivable he might get Crabbe's ~30 minutes/game, and that we might be better off.
I said that it's arguable that with the same amount of PT this year, Layman might conceivably be better now than Crabbe is. It's an unknown hypothetical, so there's obviously no way to prove it one way or the other, but it's certainly not out of the realm of possibility.
It's conceivable, sure. Likely? I don't think so. The evidence is how well the same idea worked with Vonleh last season.
The guy was 47th pick, a 2nd rounder. Not a bad flyer at that spot, but a 30MPG guy this year? Unless he's showing it in practice (we don't see that), he's not getting PT.
My observation is that 2nd rounders can develop into contributing players or even stars. The stars show it right away and earn minutes. The others develop by getting increased minutes over several seasons - see Crabbe. At least Crabbe shot .400 from 3pt as a rookie, a precursor of things to come. His minutes: 7/game, 13, 26, now 29.
Layman is shooting.227 from 3, the worst PER on the team, lowest TS%, poor DRtg, etc. If he showed he's good at any one thing that helps win games, please explain it to me.
If he were CJ, a highly regarded 1st round pick, acclaimed to be another Lillard, there might be a good case for big minutes right away. CJ was kind of buried behind Wes, who was a proven 2-way player with good size for a SG. He also missed a lot of games due to injury. He showed on the court, and in practice, he is more than good enough to start.
NO was willing to dump the starters and hand the starting spot to CJ, with the expectation he'd rise to it. I don't imagine a scenario where he's going to hand the job to Layman in a similar manner.
That's my analysis.