Why does to computer dislike Bxa6 in the benko?

So, ive been studying the benko and the computer dislikes Bxa6 and instead says to delay the capture for awhile. 

if you take it the eval goes from .6 --> 1.5

why is this?

bumping this every few hours

yeah but the computer perfers this

rather than immediately capturing on a6? why is this so?

Nice

The engine only sees the short term. Personally I don't bother capturing on b5. There's no point helping black take over the Q-side because the game will probably be won or lost in the centre. If you're going to take on b5 then main line is taking on a6 and walking the K to g2 or h2.

if you were to look at the 2 main lines and compare them to computer analysis, you would see that one is considered much better for white than the other

so why is the main line capturing on a6 before e4 rather than what is best; delaying the capture on a6

+0.6 if you delay +1.5 if you capture

That is a weird statement. Very weird. A decent engine at a decent depth sees so many moves ahead that it's certainly not short term anymore.

Also, I don't really get what Turtle is trying to do here. Openings are the weakest area of engines, especially of a super weak engine like chess.com's built in stuff.

ok

but why does the computer hate Bxa6 so much? as if its refuted?

i mean +1.5 is alot compared to +.6

Which engine? What depth? The result will vary depending on those factors.

Also, it is completely unclear to me what move you're talking about. Move 5? Or 6? 7? 8?

If you are referring to 5...g6 instead of 5...Bxa6, then this is not something the computer has invented. My old books also recommend that Black should wait to capture a6 until White has played Sc3, and if White omits Sc3, Black should eventually capture a6 with the knight.

If you are referring to 6...Bg7 instead of 6...Bxa6, it is because the engine sees some messy variants that it rates better than the traditional continuations. It is very hard to understand for a human mind. But the engine don't like a lot of traditional Black openings. However, I wouldn't be surprised if the perfect computer will again play 6...Bxa6.

Don't be to affected by engine evaluations. They don't mean much at our level of play.

The reason for this is that bxa6 releases some of the pressure on Black's position and allows Black to easily develop their pieces and potentially coordinate their rooks on the a-file. Moreover, capturing on a6 weakens White's queenside pawn structure, making it vulnerable to future attacks.

Instead, computer engines often prefer moves like 4.Nf3, which maintain the tension in the position and keep the pressure on Black's position. By delaying the capture on a6, White can focus on piece development and consolidating their position before resolving the situation in the queenside.

also

knight goes back to f3 and whats d7 bishop doing? most it will get is bg5

and if that you might as well play Bd7 to start with

i think the issue with Bxa6 is something like this

Nb5 is just a pain as white blocks up the a6-f1 diagonal and can prevent counterplay for awhile

but the Qb6 line is not as active but i guess can still give black a decent game

Have a look at what moves Black can no longer play if he makes an early recapture on a6.

If Black ignores the Pawn on a6 temporarily and instead plays g6 and the line you've given above, then he gets to play Qa5 in a position where the pin on the c3 Knight (and the resulting threat of Nxe4) forces some concession out of White.

It's not as if the Pawn on a6 is about to escape... it's attacked four times.

If instead Black were to recapture on a6 right away, he will not have the tactical threats of pins on c3 and loose Pawns on e4.

also ive realized that the delayed taking can result in much more dynamic games. the computer recommends repeating in the main lines

also the computer recommends e6 (not very common in the fully accepted benko) which opens up central play for white compared to only d6 where central pawn play is very difficult to have without causing issues

Are you familiar with the Leningrad in the Nimzo-Indian?

It might have some bearing on your Benko theory-crafting.