MJ, really
I have no training or authorisation to examine the standard of SEP pilots as a FI.
Now I happen to be an FE, but before I was and when I have my FI hat on, I do precisely that several times a week. Isn't that exactly what we do as instructors every time we do a club check-out prior to PPL hire, also when we're considering sending a student solo, it's a similar situation, we assess (examine) the standard of their flying.