1800/1900 puzzles but low rapid?

Yeah, so I just hit 1900 in puzzles and consistently sit around 1700-1900 with around a 56% pass rate. I could honestly probably hit 2000, but my rapid rating is stuck in 600. Is it just opening principles that are my issues? I feel like my endgames are pretty good, but my openings and middle-games kinda suck.

I don’t really play any openings, but I try to stick with the London, Italian, Guico Piano (or whatever it’s called) and the Piannisimo version (no clue what it’s called LOL) for white. For black, I just try to play principled since I don’t know ANY openings.

After the opening, I feel like I enjoy tight, tactical positions, but I never know what to do. Any tips on studying mid-game principles too? Or any good openings for ~>1200?

Looking at your last game, 59337056797, you're doing well until move 10.

You are ahead of your opponent in development, so you probably want to open up the lines. Just eyeballing it, I can't see any good outcome for black, regardless of how he decides to play it.

Instead, you decide to close the centre and kick the knight (not exactly a blunder) and your opponent blunders with Ng4.

Here's a 600-strength tactical puzzle. Find the best move (two moves, if you want to be picky) for white.

 

If you put the game through an engine, you can see other tactical blunders too, so regardless of your chess.com puzzle rating, the in-game tactics are, well, not 1900...

 

Of course, if you are playing 10-minute blitz games, you don't really have time to think about your moves.

PS As you say, a good idea would be to start linking opening to middlegame. If you play London for white, books like Gambit's "Win with the London system" provide plenty of model games to play through.

But your main problem at 600 is blunders.

So for the most part if I get a development lead, I want to open up the board and let my pieces have more control over the open space? 

Generally, yes. 

If your opponent is behind you in development, opening the lines gives you more control and allows your far-reaching pieces (rooks & bishops) to join the attack. Your strategic possibilities  are greatly improved, and tactical combinations just seem to happen by themselves, as all the pieces can come to the "right" place. Very aggressive, tactical players can even sacrifice a minor piece for a pawn if that gives them open lines & very active piece play! 

This is the logic behind the opening principle "Develop your pieces quickly".

Another principle is to develop your pieces in such a way that they work in harmony and are not left hanging, so while you're throwing your pieces out into the attack, you need to try and keep them protected and co-ordinated, which costs you time and slows down your development. If you have a natural positional sense of where things belong on the board, you'll do this instinctively. For the rest of us, studying classic games by strong players gives us the idea of how to play so you play fast & active, but not too fast and loose. Striking the right balance is very hard.

 

Tactics wise, I think after the black knight's move above you should have spotted that the knight is now trapped (600?).

Black has a counter-attack with dxc (800?)

but it doesn't really save the game for him (Bxc4; Ng4 is still lost) (900?).

Taking the Ng4 straight away is not the best move for white positionally, as dxc opens up the diagonal for Bb7, improving it's quality.  At the moment, Bb7 is looking like a sad tall pawn, so you probably want to keep a black pawn on d5, hence, cxd for white first, to prevent dxc by black, then h3 to take Ng4 at first available opportunity (1100?).

1200+ you'd be looking at every possible retreat for the black N (after h3, he'll go out with fireworks, taking a pawn and doing as much damage to your position as he can), assessing if taking it at this point is really worth the positional damage, and checking if black has any chance to save that knight, or whether you can delay the h3 attack and spend a few more tempi improving your position before finishing the knight off.

Sorry, just eyeballing this and haven't checked this logic & variations on a board or with an engine, but this would be the thoughts going through my head in a time-pressured game. Analysis above might be full of holes - I'm not good at short time controls.

Ratings in brackets are just a finger-in-the-air guess.

Lol, yeah I wouldn't do much better anyway, so I couldn't tell you if there were any flaws in your analysis. The only thing I think I would do differently after pushing the h pawn is to play Qe2, trying to open up possible queenside castling, since I enjoy castling long more. The knight is always kinda immobile, so I feel like I wouldn't need to snap take it.

I don't even think I registered that the white bishop on b7 was stuck in this game. I probably saw it, but I highly doubt I even recognized it consciously. Most of the time, I gloss over the tactics involving blocking off the opponent's pieces with their own pawns. Majority of my games though, I do look to trade off bishops if I notice my opponent has a lot of pawns that are the same color (for example, I want to try to capture my opponent's light-squared bishop if all of his pawns are on light squares). 

I feel like my tactics in game are definitely a little worse than puzzles, mostly just because of the "there is always a best move" in puzzles. I have noticed that when analyzing those positions, I would probably play much simpler moves in game, and not look for tactics CONSTANTLY. Maybe if I were in a classical match, I would decide to play something more aggressive, or something that's harder to spot in rapid, but I simply don't have time for anything more than 10 minute lol. I'm in school 90% of the time. 

LOL SAME IM 2000 ON PUZZLES AND 600 RAPID

puzzles is just showing you one part of chess. That is, find the winning move in this winning position. However in an actual chess game both players start from a non winning position and its your job to develop and find a strategy that might get you into a winning position.

So in actual chess you have to do a lot of non winning moves that are at the same time not mistakes, not loosing and not blundering and that is not easy.

What I find working is to play slower games, analyse the games after, and to watch stronger players to pick up on their strategy. It takes a lot of time to get better.

When to play on kingside, when to play on queenside, when to castle, should I castle kingside or queenside, should I go for a pawnbreak, should I sacrifice a pawn for activity or to unluck a square, pushing a pawn to unluck a square. Yeah ton of things to learn.

Puzzles ratings are very inflated and shouldn't be taken too seriously.

inflated compared to what?

I don't think one can compare rapid versus puzzles rating, since they are two very different things.

A suggestion that I can't follow myself? Play the 3200 ai at your very best.... But don't just play! Pay attention to it's tactics and strategy's. A bot hardly ever has a game plan cause it uses it's moves just to counter yours like if you devolop then it's counter is to force a bad position if you attack their king then it promotes king safety and so on and so forth....

When you do puzzles, do you rush them or do you take your time and get them right? 

 

So then why rush your chess game and compress it into 5 minutes, eliminating all opportunity to think?  Playing speed chess will not help you to improve at the real game of chess.