There are a few questions about contacting authors of papers when acting as a referee, but my question is related to the review of conference proceedings. After reviewing a paper which was submitted as a work in progress (meaning that it is in the early stages and the author intends to receive feedback at the conference) I am wondering whether I should approach them at the conference and reveal that I was a reviewer on the work. As I reviewed the paper I thought their idea was good but there are lots of small things I've commented on; perhaps since I reviewed the paper I have read it more closely than others will.
So the conversation would be,
Hey I read your paper, such and such title, as a reviewer before the conference and I thought it was good. I've been thinking about your ideas since then and ...
I can obviously approach them noting that I've read the proceedings, but should I reveal my work as a reviewer?