I agree with most of the posts about the practical knowledge part of the CFI needing to be tested. I have been a CFI,II, MEI. I am an instructor in the B-52. I don't find that much difference in teaching either skill. If I can teach a guy to air refuel, land, takeoff, low-level, and bomb, what makes anybody think I am lacking the skills to teach and engine out landing in a 152? A similar argument, though false, could be said for a guy with an MEI who learned in a Seminole. Well he would have no time in a twin otter but would be perfectly legal to teach in it. You have to draw the line on thinking somewhere. Hopefully, most of us have enough brains not to teach in something we are not experts in ourselves.