Sometimes I interview candidates and inwardly cringe when they respond. There are so many that I wish I could help. I can speak personally for me and how I operate. If it's an internal candidate, I talk to them as I walk them out. I tell them to feel free to call me sometime and we can talk about interviewing. There are so many external candidates I would love to help, but unfortunately I just don't have the time. I have, occasionally, given them my card and met with a few.
We interviewed six people today and I was doing my best to drop hints about how they can get more experience to increase their chances of getting hired. So many times I prompted for them to give more details.
I'm happy to say that there have been some employees who have gotten promotions after speaking with me, but also some that realized perhaps they should stop applying so much.
All this to say, it really depends on the HR person. I work LONG days because I spend a lot of time helping people so it's hard to get my work done. Get a feel for the interviewer and if they seem genuinely interested, ask for their card, give them a call. Don't stalk them, if they don't call back, but it's worth a try.