Dear IM Pfren,
while it is true that the subject of the OP has been considerably deviated from (and just for completeness, I'll also take the opportunity to inform the OP guy that I'm not going to tell him if my repertoire is different or the same... why give him the advantage of being prepared when he comes to play me one day??) - I still find your posts very interesting, inspiring and instructive - while containing a personal element.
The question that comes up is - how does one work on his positional chess? I know I suck in that department as Chess Mentor, which is dedicated in the higher level to exactly that ability, leaves me stumped time and time again. It gives interesting lessons, but I feel that they touch isolated, random points, and I don't feel that I'm becoming THE positional player who finds plans in every positions, knows the correct moves and ideas, where the pieces should stand, which squares are key - well of course many times I do... but in the more difficult positions, well, no...
This is exactly where a strong computer program cannot help me much, as it doesn't really matter if a certain move is +0.71 or what, even if the engine is right, if you don't understand the key plan, the key structure, the combinations behind the scenes, the endgames and how to conduct them...
So - yes, opening study, tactics training, practice - and then one does hit a wall. In your case it was in 2250. In other cases it's somewhere else, generally at some point between FIDE 2000 and FM... your advice please!
Opening knowledge and preparation has a very important role to play in grandmaster chess, and correspondence chess (I mean the modern correspondence chess, where everyone is allowed to use an engine).
But for achieving a very decent rating (say 2100 FIDE or something like that) the opening is of very little value.
Want a confession? Ok, here it goes. In my youth I have achieved a FIDE master title and a respectable 2250+ rating, working mainly on openings (I had a very good knowledge of openings I played, as well as openings I did not play). But at some point, I realised that I did not improve at all- despite my good opening knowledge, and excellent tactical skill. I had seriously worked on it, and decided that my rating was pure luck: my positional understanding was nothing to boast about, and my endgame technique was, well, dismal.
I have earned my IM status by working very hard on my positional play. True, this did not eran me more than 150 rating points, but it was enough to get the IM title.
I have also worked hard on my very poor endgame technique. There, my rating gains were rather insigificant, because of me (I usually am exchausted when a game reaches the endgame, and most of the times I play crap). BUT, the in-depth study of the endgame (thank you, mr. Dvoretsky!) has greatly helped me improving my overall understanding of the Royal Game.
One is free to develop his playing strength whatever way he fucking pleases. My obligation, as a trainer, is advicing my students, to never, ever make the same mistakes I did- and one of them, probably the crucial one, is devoting a lot of time in openings.
Understood?
leaning opening is a must for professional chess.. You are an IM becaseu you have learnt openings well... May be as you said the other important things to need to look into.. like improving as a positional player.