i would guess this to probably done to avoid leaking value of kernel registers. it might not be necessary but why don't we follow what native does? that's what the test finds anyway.
Quite possibly, yes. The test still needs a work to do to be included upstream, like we don't write such functions with "asm" at all and specifically for tests we unfortunately have to write those in binary and not as asm for portability (also can't reference global symbols).
So I don't know, from one side, yes, it doesn't hurt to deliver exact values. On the other side, when nothing is known to depend on that *and it looks not much likely that anything will depend specifically on that and not, e. g., on some proper r11 value*, extra code to add that and following Windows internals too closely may be counterproductive. We don't have any reasons to hide Wine register values from the app, we don't have security boundaries like real kernel has.