Pianorak,
You might be interested in a conversation I had with a flying instructor about a year after I got my PPL(A). I had just got back froma long XC flight, one of many...I spent the first year after I got my PPL flying all round the country most weekends with another newish PPL. This instructor had left while I was still struggling with landings, and had just dropped in to say hi to everyone.
Whirly: Hi
Instructor: Hi. Did you ever go solo then?
Whirly (somewhat confused by the question): Er...yes.
Instructor: Really? Oh, that's really good. Well done!
Whirly (feeling ever so slightly patronised): I got my PPL over a year ago.
Instructor: Really? You got your PPL! That's great!
Whirly: Well, it is a while since I saw you.
Instructor: Yes, but some of us thought you wouldn't make it.
Whirly (now a little annoyed): Oh, really? who?
Instructor: Well, me, for a start.
Whirly: Ah, you. I see...
The moral of my story (and yours) is that being able to teach flying doesn't mean you have brains, or that you know about people.