If it didn't happen last window, I don't think it will happen next window too. I am a realistic Spurs fan. The window of opportunity was last window for Isco, when we were ahead of other clubs to take him. But he wanted to give one more season at Madrid. He has made up his mind by this Jan, obviously his agent is going to tout him to every top club in world.
Its hard to see how he would end up at Spurs, for more or less same salary.
It would be nice if it happens but not holding my breath and not too bothered if we don't sign him. We currently have imo the strongest midfield in the league so I would rather focus on Forwards since any time Kane is out or having an iffy game we struggle. Our other forwards just don't produce.
You do it by training harder and showing more skill and teamwork than the players that usually get selected. Then on the occasions you play, you make sure you are the man of the match. Isco hasn't been able to do that so either he is just not as good as the other players in the starting 11 or he isn't able to really fight for it.
Personally I think he looks great in Spain but I have my doubts as to how he will take to the Premier League. It is a different style of football and may not suit him so he probably wouldn't just walk into the team. He certainly would not be used to somebody like Alex Bruce sending him flying and the ref waving play on.
Mate, the guy trains with Pepe and Ramos, both partial to a bit of nasty kicking, and dish out far worse than anything Alex Bruce has done (An odd example considering he's rarely kicked a ball in the PL).