Johnlock meta: John deducing stuff

I was watching "The Great Game again, and in my favorite scene, the one where John tries to deduce Carl Powers' trainers, you kow that is where Jim appears for the first time, "pretending" to be gay.
Well, in this scene John gets a bit angry because Sherlock has deduced Jim is gay in front of Molly. John thinks is cruel, rigt? Well, when Sherlock says Jim is gay because of his level of personal grooming, John says "Because he puts product in his hair? I put product in my hair!" XDDD. Then Sherlock explains all the clues that he saw that said to him Jim was gay, and John ends believing him, I think especially because of Jim leaving his number under a dish. John reacts with jealousy.

But that's not what I'm interested in. This is old water under the bridge, so... The thing that I love here is that after John says to Sherlock that saying to Molly Jim was gay wasn't kind, they stay silent for a while. Sherlock looks sincerely done with it. John doesn't understand he has done a favour to Molly. I personally think it was the right thing to do, but in my case I would have said the news to Molly in a kinder slower way. Sherlock was just showing off. But that's not what I care about here. About this scene I think there's something else.
John tried to deny Jim was gay by criticizing Sherlock's generalization about the personal grooming Sherlock mentioned. We can say we have that clear. The causes could be because of his own sister, but I don't think most of viewers stop to analyze that. They think John is mad at Sherlock because he's being cruel with Molly, but there's more under that. We could say that it's also about John's bisexuality and the general tendency of people to generalize about people. I would be mad at it too.
But after Sherlock deduced all that stuff, I think that may be Sherlock could have got angry about John trying to reject his generalization on people, but not because of John's criticism, but because of John trying to deduce gay people. I can see Sherlock getting angry about it like "you can't deduce gay people, John. I can. If you could you would have deduced me." And I think it could be a clue from Sherlock thrown on John's face. Sherlock uses product on his hair, anyone can see that. Sherlock has a high level of personal grooming. I mean, he's in a lab, in a suit, without a wrapper on him. It reminds me a bit of Barney Stinson (from How I met your Mother) sleeping in a suit-pajamas. Well, Barney is not gay, but he has a high level of personal grooming.
Sherlock got angry because John dared to say that Jim couldn't be gay because it's wrong to generalize about people's looks, and then we have Sherlock challenging John to deduce the trainers that later he identified as Carl Powers'. Why would Sherlock do that? Because he was pissed. He gets pissed when "stupid people" dare to deduce stuff and correct him about his own deductions. I mean, when Molly corrects him about her weight sayin "Two and a half", Sherlock says all childish "Ahm... three", again.
I mean, I can see Sherlock thinking: "How dare you to deduce stuff, John?" Especially gay's stuff. You don't know a thing. If you could deduce stuff, you could have deduced me".
Also, another thing I realized. Sherlock kinda smiles to himseld when John says "Because he puts product in his hair? I put product in my hair!"

Closer:

This child... XDDD
I can see him thinking "Yes, John, gay people use product on his hair. You have the proof in front of you. hehehe you can't catch me. Try to deduce me, John! Try!".
I think that this is another clue of Sherlock not knowing a thing about John's sexuality. Well, knowing. Sherlock makes assumptions about people, like with Harry. He thought she was a man married with a woman. Sherlock must think, now, that John is straight because he has dated women.
Sherlock doesn't have a clue, at least at this point in the tvshow. But I like to think that even until now, until the last episode, he doesn't know. Why I prefer it like that? Because DRAMAAAAA.