How far can you get practicing only tactics?

Just wondering. If you practice only tactics with a general understanding of the various opening systems and some experience but no therotical mastery of endgames and you practice only tactics basing your play upon it how much blitz rating would you be able to achieve on chess.com.

The problem is "general understanding of opening systems" means different things to different people. Vastly different things.

If someone were introduced to chess as a puzzle game, and told it's not a game that two players play, but just a book of puzzle positions, and then after years of solving tactics given a few hours instruction on some openings and thrown into live chess blitz, their rating would probably be very low. I would guess below 1500 easily. Blitz also requires you play strategically sound moves quickly. It requires endgame technique. It requires defensive play and practical play that has nothing to do with tactics.

But if all a person did was play blitz and work on tactics, while very slowly working out some basic openings for themselves as they go, then they could be rated very high with (more or less) "only" tactical ability. Probably something absurdly high like >2500, but obviously they'd have to be very good at tactics and purely through their experience of playing pick up knowledge in other areas.

Thanks for your answer @stiggling. Very informative. Resisting the urge to argue, I would just like to pose a question. See frankly I hvae given up on OTB long time control chess. If I want to get better at 5 min bltiz what course of action would you recommend for me. I do have Chessbase 14 and a Platinum membership here. I hvae ordered the digital version of Chess informant and  I am awaiting delivery.

Should I go through tons of GM games or what should I do?

You can think of the "tactics only" player like a person who has played games similar to chess (like shogi) and is very good tactically and very good calculator, but knows nothing else. This person would be rated very low in a blitz game.

And of course my >2500 estimate would be the very high end. Most people of course can't seem to get above 1200  (somehow the chess.com average is very low).

But yeah, to get better at 5 minute chess, just improve at chess in general.

If you've given up on long games, then be sure to select your openings to favor things unbalanced positions and initiative. In blitz initiative and confusing your opponent is worth a lot.

It could even start really boring like a stonewall as long as you get to attack later. You'll just have to pick the types of openings you like, but I'd go more towards king's gambits than stonewalls.

Yes. I do my share of opening work out of interest rather than necessity frankly. I have many powerbooks for chessbase/fritz(nimzo indian, open games, anti sicilians, french etc.) and I look at them from time to time. I am doing some puzzle rush these days and it has increased my tactical awareness.

Anyway, if someone can let me know what it is that I need to be doing other than tactics then that would be great.

Compare chess.com's list of top 10 blitz players to this

https://2700chess.com/

The answer to what else to do besides tactics is everything. Being good at chess in general (and playing blitz often and being relatively young) will make you a good blitz player too.

Endgames are important for example because you need to know how to win and draw technical positions without using any time on the clock.

Knowing this will also make your middlegame evaluations more accurate because you'll know which pawn structures and piece trades are good and bad for you.

probably 2500-2600