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An Opaque, Default Lit material with a single node: 735 shader instructions?

I’m trying to diagnose some unexpectedly poor GPU performance, and I’m really confused by the shader instruction counts being reported in the material editor.

I’ve got a test material with a 100% default setup, just feeding a static (0, 0, 0) into the Base Color, and the stats in the Material Editor report 735 instructions in the pixel shader and 6 texture samplers. Do these numbers make any sense at all?

This is using 4.20: the last project I worked on used 4.16, and I’d have gotten maybe 70 or 75 instructions from a similar material on that project. (I’m also noticing drastically slower shader compile times now that I’m using 4.20.) Any idea why these stats are so insane? Are there any circumstances under which a simple do-nothing material could be reasonably expected to produce such a massive shader? Should I not trust the stats being reported in the material editor? Is there a demon in my shader cache?