I might be wrong about this, as I'm fairly new, but to me the whole point of a GFE party is to allow yourself to have feelings of intimacy and closeness. The danger in my view isn't in having feelings, but in not being able to determine fantasy from reality afterwards.
Not from my perspective.
The term girl friend experience meant to have sex similar to one would have with a girlfriend with kissing and performing oral sex on her. At one point in the past many ladies did not allow kissing. Some did not allow oral on them. I am talking about the late 1990s/early 2000s.
I don't want to think you would want to try to have feelings of intimacy and closeness with someone who you are paying for sex and isn't going to be in your life unless you are paying--especially someone who might move on without notice.
These feelings may come about even though intellectually you know that the two of you can never be together. It has certainly happened before since logic doesn't dictate emotions and sometime these things happen whether the sessions are GFEs or not.
But I think it would be foolish and playing with emotional fire to to encourage the feelings in yourself.
Intimacy might not have been the best word, as it's a bit of a loaded one. Really, I mean more of a closeness like you'd have with a friend (or in this case, friend with benefits). To me, it's the difference between a purely mechanical situation and being able to enjoy things on a more personal level. Kissing and mutual pleasure, although not necessary, do help to facilitate that. I certainly don't mean to say approach it as if the courtesan you're hiring is your actual girlfriend, as that would definitely lead to emotional upset.
For me, though, I have to find a middle ground. It can't feel too intimate or close, as that would lead to obvious disappointment. Yet, it can't be so foreign that it feels like the equivalent of a sexual oil change; just something routine that happens every now and again.
Thankfully, in my case, it takes quite a while for me to really open up and be totally comfortable around people, so I have a bit of a built in defense mechanism. That isn't to say it can't or won't happen, but I'll cross that bridge when I come to it. Worst case scenario, I'll be bummed out for a little while and have to find someone new to party with.