The patting on the head is a reference to the im@s touching scenes. mariokirby wrote that the touching scenes can be an issue by itself, but most of the time it actually is patting the idols' head, bumping fists and stuff like that.
Giving something like a high-five is no problem. What I was referring to is touching other places that become an issue (especially with an underage girl) besides chest touching such as face touching, chin stroking, hair stroking, leg/thigh touching, etc if we're giving this a T rating. Even if the intention is different.
I don't know how bad head patting is, but if hypothetically it's not bad, but then the problem is that you could touch another body part and still get another response.
Remember, the Producer represents you. You are the one doing the touching/stroking not someone else. With all the hot topics going on in the gaming industry, things have become a little stricter. What's more tolerant in Japan is not that tolerant in the US.
Of course, the reverse is true. Violence is more tolerable in the US than in Japan. An example would be Metal Gear Rising. In the JP version, the game was censored to have white blood while the US version kept the blood red.
So, different countries have varying degrees of tolerances, and it's something you can't really change.
Tolerance for Violence: Europe has the least tolerance, then Japan, then Australia, then the US
Tolerance for sexual themes: the US is the least tolerant, then Australia, then Europe, then Japan
Tolerance for drug use: Australia is the most restrictive, then Japan, Europe and then the US.