Maybe you can't fathom how this could be possible but some women can tell the guy how hard they want it without having a conversation beforehand. Also when you meet someone you get a an idea of the type of person they are before you have sex so you can use that as your baseline I guess.
Eg, if I take home some slutty type of girl thats grabbing at my cock within minutes of meeting her and shes got heaps of tats on her neck and arms, studs in her face tounge nipples and clit, before I've done anything I'm gona ramp up my baseline just on first impression. If i was with some real cute quiet petite shy chick, I would start off much slower, if she wasn't giving me decent signals I wouldn't expect the quiet shy chick loves it rough from the start.
Don't judge a book by it's cover. That girl with the tats and peircings who is sexually liberated might not like to be fucked in the mouth...
Just because a girl has tattoos and piercings doesn't mean she's a slut who likes it rough.
That cute shy girl might like it rough, how do you know? I've been called cute and shy. I have no tattoos or piercings. My guy wouldn't have known I like it a bit rough if we hadn't talked about it and established the trust we have together. The first time I gave him a blowjob he was gentle with me, he knew I was shy...we talked about it before during and afterward, he asked if he could fuck my mouth more next time, be a little more rough, and I said yes.
This thread has become quite nauseating...obviously you're going to do what you want regardless of our opinions.