Two concrete questions about Sicilian Kan

My 2 questions are inserted inside the diagram. The first one I think I figured out, but I would like a confirmation and maybe some added explanation. If you have experience playing black and/or white side of Sicilian Kan I would like to hear your input. Thanks in advance.

To answer your first question, I believe when top players use the Sicilian they're playing as offensively as possible to avoid a draw (as opposed to a Berlin or something like that). For black that position looks very equal but white is a very little bit slightly better in my eyes and I think there's more efficient ways of shooting for a draw rather than playing this variation of the Kan. If they were in a must win position they wouldn't play this too, Dragon and Najdorf are both sharper variations with better prospects for black than the Kan in my opinion. You're higher rated than I am though, you probably know more than me on this

i think its simply because black doesnt mind playing hedgehog structures. its an ambitious way to play where there is alot of room to outplay your opponents

That is the closest to what I thought about that position. It probably looks like a more ambitious try to play for a win with hedgehog structure but I thought there may be more to it. You might be right. I like those hedgehog vs Maroczy games, I only played one game like it as white, though it wasn't even Kan variation.

Thank you for your views as well. Kan is a bit different, that is the truth. Both black and white needs to find a way to open the position to their advantage. Kan is a Sicilian more suited for a strong positional player that wants a bit different game then a racing lunatic games of English attack Najdorf or Yugoslav attacks Dragon games out there. Black is a bit cramped but white can't just go forward without thinking, it is tricky for him as well. I am mostly looking at it from the white side here.

Interesting questions! You have made me think about this lines. I like the line 7... Nxe4, seems good for black.  Thanks .

No problem.

Your answer for nxe4 was a misdirection. its not f3.....but clearly bd3.

The second question is a3 is played to stop Bb4. After black plays qc7 its helpless, and blitz only. 

Thank you for taking the time to answer.

After Bd3, black plays Qxd4 and is a pawn up. Of course black is a bit undeveloped so white has compensation. The engine shows around +0.3 for white there. After for instance castles for white and Be7 black seems perfectly ok (white is of course slightly ahead).

The second part I didn't understand, specifically this:
After black plays qc7 its helpless, and blitz only. 

You mean if white doesn't play a3 it is hopeless after Qc7? Why specifically, could you explain, that is partly why I opened this topic? I am asking because even without a3, white seems fine if black decides to exchange his better bishop for his knight.

For instance I found (in the online database I use) 7 classical games by 2400+ FIDE players in this position:

White has won 2 out of those 7 and the other 5 were drawn. When I look with the engine, it says white has a tiny edge (something like + 0.2 which seems like a normal opening advantage).
And that 8. 0-0 is the best option for black. White can play 8. Qd3, keep the pawn and he scores even better there.

That is why I think that the purpose of a3 is not just to stop Bb4 (as white doesn't seems to be worse even if black plays it), but only partly because of Bb4, and perhaps even more so he can play b4 and make his play on the queenside.

So first part, bad engine. Maybe you used chess.com....actually its +1.2

You have to keep with the engines...things change.

I know about this line, that is a going towards hedgehog structure that is mostly played by black. 

My questions were aimed at potential deviations for black. As I could potentially play white side of this, I just wanted to know if I should be worried about Nxe4.  I didn't use chess.com engine.  Anyway I listened to ChessDojo a few days ago, where IM Preuss said that giving up black's dark square bishop would be a mistake in that other line (if black plays Bb4 on move 6 instead of Qc7) because black has almost all of his pawns on light squares (that is why I concluded that as white wants to play on the queenside anyway, he plays a3 as a multipurpose move that restricts black's bishop and prepares b4). 

As for Nxe4, from other source I've heard that was the possible line and that black is fine (and well there were some longer games there which usually ended in a draw especially for high rated players, though it is rarely played that is true).

But, perhaps you are right, after all, I don't really now too much about the position. It could be much better for white after Nxe4. It seems like a more interesting game that standard line you've put for sure. In any case, thanks again.

7... Nxe4 seems very risky, for example a sample line by engines:

Yeah white just looks a lot better in that position

Yeah now that you've shown me the entire line, it visually seems bad for black. White has a lot of play for that pawn. And one very interesting thing. The engine I have shows almost all zeroes at first but when you put in the whole line it changes its mind and says white is much better. 

Perhaps Nc6 is somewhat better for black than Be7, but probably black shouldn't go for this line. 

In any case, this is one less thing to think about if I ever get this position as white. Thank you for the contribution.

I think 7a3 is pretty much about preventing Bb4. If you don't think Bb4, and BxN is anything to worry about, which might be true, then 7Be2 might be worth looking at. Kotronias has a book where investigates playing more aggressively against the hedgehog. Aiming for f4, and g4-g5, rather than a3, and f3. https://www.newinchess.com/attacking-the-flexible-sicilian

The reason I just think that white (some strong player playing white that is) is not that worried of Bb4 is because black could play it the move before as well. And I tried playing out that Bb4 and then taking the knight on different moves. Engine is not thrilled about the resulting position for black. I mean, it is not terrible either, but it goes in some instances from +0.5 to +0.8, so white should be at least ok. The reason I think that happens is because of the semi open file and because of the fact that was a better bishop for black. At least that is the way my patzer inner self understands it (I could be wrong of course).

But of course, the game is pretty different if that happens. In many cases white wants to push those pawns, so if black doesn't play Bb4 before a3, white takes away that option completely and has a clear plan of playing on the queenside, like it usually transpires in some of these games it seems.

Now, I said that from the perspective of someone stronger than me. Personally, I am a bit obsessed about keeping a nice pawn structure and even though I am aware that there are some upsides to doubled pawns in some situations, I still rarely choose to play that way.  I know that is one of the things I will have to gradually change if I wish to be better.

Thank you for the input.