If you are asking: if you are using SVM for your root devices, and then you enable stms, will the underlying devices change that make up the metadevice. The answer is yes.
example:
mirror d10
c0t0d0s0 d11
c0t1d0s0 d12
you run stmsboot -e (sparc only)
for x64/x86, you modify the file...