I've recently started giving interviews for my place of work, and sometimes I end up interviewing candidates who make mistakes that can be corrected without a significant amount of work. As a specific example, occasionally I will get resumes that are upwards of five pages for a mid level developer job, the fix being trim it down to two pages (at least). Perhaps they repeat a lot of information, or there's a lot of fluff.
Is it improper for me to give this feedback to a candidate, especially unprompted? I've asked others in the office and they've said that they tend not to do it, but they don't really know why (just that it feels like something they shouldn't do). I'm on the fence because for one, what do I know? I don't want to give someone bad advice. Additionally, it does seem like it could cause hurt feelings, and could maybe spiral into something that I'd rather avoid.