He just had to blow for the next throw in as the previous throws were so obviously foul , the crowd were going mad , I'm not saying he was right to do it
Gvardiol's weren't foul throws though. Read my earlier comment on that, it has a video explaining what the laws are on it.
I agree his arms look a bit flimsy in his technique but what was it you thought you saw that made them foul throws?
The first moan they had was for the one at 17minutes 20 seconds of the match. Both feet behind the line, both feet stayed planted, the ball started behind the head and came up over it with both hands on the ball. As I said before there's nothing in the rules about the point at which you must release the ball.
The second one is at 29mins 50 seconds. Their manager is between the camera and the player but you can see he's behind the line, it starts behind the head and his feet stayed planted. You can see Bernardo shaking his head confused at the ref there.
Edit: There was another the Luton fans moaned at on 37mins 30 seconds. That was the same as the other two. I thought that was the one he blew on, my mistake on that.
Even the commentators said they didn't see much wrong with Bernardo's(44mins 34 seconds): "He has a point" I seem to remember them saying, without making too much of a fuss about it.
This is from the Athletic:
Although
Kyle Walker came out onto the pitch still debating the foul throw laws with referee Tim Robinson,
who signalled in return that both hands had to be behind the head at release but seemingly did not apply that to Bernardo Silva’s first-half effort, City quickly forgot about the opening 45 minutes and put things right.
I didn't catch that during the game but apparently that's not in the laws of the game, so what is the ref talking about? I'll also say of the two Gvardiol throw-ins I did get a view of when he released it, he seemed to be letting go of the ball towards the back of his head anyway to my eyes. Maybe he does need to work on the technique, if only to stop people trying to claim foul throws.
Also, look at the goal kick decision around the 43:10 minute mark as another example of the ref letting the crowd make his decisions.