If it is a checking detail you should brief what you want them to do then say nothing to them for the check.
I actually understand why alot of ppl's do look for conformation all the time. Its basically because they get retrained every time they get into a cockpit with a new Instructor. They have got it in the ear that often they don'y know really what to do in a check.
Now the converstion
1. Brief it
2.Demo it
3 Do it.
If it all goes well you won't have any issues, its when they have issues and you have to do "instructor" stuff you might (I say might but I reckon you won't have an issue GTE) come unstuck.
The Flying Instructor's Patter Manual
This book gives you the method that we break down exercises and put them back together again.
The checkride bit I am quite happy with experenced PPL's doing but the converstion issue is the bit I feel is best done with someone with a ticket. I have had some right tulips doing conversions and shall we say the skills I have from teaching people how to land for the first time have been used in converstions to save a couple of nose gears.
And I will admit the examiner bit was over kill.