Well, I explained my feelings on it in the post tbh.
No, it isn't in the rule book but every keeper gets to set up a wall and as an ex-keeper I think it is a shit trick to say yeah you can take it quickly and have a free pop on an empty net.
Why doesn't it happen every game if it is a fair rule?
Sort of like the Rugby at the weekend, did you watch England's game?
Ref tells England Captain to go and have a word with his team about their discipline, Captain goes under the posts brings all the guys in to tell them what the ref said, Ref then allows Wales to chip their penalty into the corner with the onrushing winger unmarked and nab a try as no England players are about, Ref then tells Captain, I gave you enough time to tell them, when blatantly he did no so thing.
It is a cheap shit trick that the ref has to be asked to allow, the ref can no, so in effect a quick freekick isn't a given, it is only a complicit action with the ref's permission, see KDB for a further example.
As for the ref's making up the rules, that happens on a match by match basis, see our offside v Villa for that, none of them really knew that rule, the penalties given, the cards given or not given for the same kind of tackles are decided on the whims of a ref, despite them having firm guidelines.
ps I didn't say he made the correct decision to blow the second time btw, he should have stood by his first decision but he panicked knowing he would be highlighted later for controversy, which ironically he has made worse lol