I don't think I would advise him one way or the other. Instead, I'd make sure he has an understanding of all the ramifications and repercussions that come with both sides of that decision. Ultimately, it's something for he and his YF to figure out.

Obviously this doesn't always end badly. Gay literature is filled with stories of such relationships written by men who look back on those experiences fondly. But in the current environment, it's very difficult to justify the risks.