Update... I have been at university today and spoke to a PE trainee who works at the school I am applying for, the Assistant Head has resigned his SLT post so definitely won't be on panel.
However this does not bode well for a happy cohesive SLT and school, he was not complimentary in his assessment of the Head. There are also 3 posts in my subject which is because so many have left. Eek.
But I will still apply just for the experience but I cannot cope with another nightmare SLT and head.
I don't know specifically about teaching, but I would have thought it's entirely usual to use what you already know about a previous colleague in a recruitment situation. I don't know why there would be a breach of confidentiality - if his boss knows you worked together previously, why wouldn't he ask his opinion of you? It's what networking is and how most recruitment is done in my industry.
That said, it doesn't sound like your situation would necessarily work against you. You got on personally, he knows you were working in difficult circumstances and he knows the effort you put into turn things around. All good.
I am about to send off an application for an English teaching post, my first one, I am currently on the GTP. (I am super numerary so no posts in my training school)
My issue is that the school I am applying for employs an Assistant Head who was seconded to my current school as a Deputy while we were in Special Measures.
My former role was middle leader for behaviour and attendance and during the time he was at my school, I was in informal capabilities for a short period (along with the majority of staff!)
It was all fine and I was only in for half a term, never went any further but I am really concerned that he might discuss this with Head or it will go against me if he interviews me.
I think he knew I was in it, he certainly was part of the monitoring I was under for that period.
It was a very difficult time for me, my partner's business went under during the previous half term, we almost lost our house and so I wasn't performing as well as I might have but I have 9 years of outstanding performance in a pastoral role before that and am already judged at 'good' against Ofsted observations so hopefully to be graded an Outstanding by June.
Not sure what to do ...should I still apply? I actually got on very well with him personally and have seen him since and all fine and pleasant conversation was had!