What is the chance of getting exploited in a hole in your repertoire ?

I'm developing a repertoire right now ( actually checking my current repertoire and strengthening it ).

And I decide to don't deepen it so much in trashy lines.

( 1.Nc3 or 1.f4 with black etc. )

But deepen it in main lines like Marshall Ruy or Grunfeld.

Is it likely to getting beaten by an opponent who knows my repertoire VERY WELL ( suppose that he hacked my PC )
and prepare a line specifically for me ( computer-assisted ) in my less-deep lines and beat me with a winning position by move 15 ?

( PLEASE !!! Don't say he can outplay me in the middlegame or endgame. I know that. My aim is to keep an advantage MORE moves as possible. [ I couldn't win a +2.5 position on move 10. I played a -0.1 move instead. AFTER THINKING FOR 20 MINUTES ! This is why I want to deepen my repertoire.] Like waiting for a blunder or mistake. )

Really though at low levels I don't think deep repertoires matter, you need to know the principles of the opening you play so you can exploit any mistakes your opponent makes, it's impossible to prepare for every move your opponent can make even if you play only one opening, and about exploiting holes in your repertoire - that kind of stuff happens at professional levels, but by the time you get there you will have much more experience in your opening.

You can't know every possible position through the first 10 or 15 moves. You're going to get in positions you've never played before out of the opening regardless if you study lots of theory. If you weren't able to win a +2.5 position, then it's because of your chess skills, not your opening repertoire. Someone could prepare a line for you, but sooner or later they will be out of their repertoire. And the better your tactics are, the less likely you will end up falling in to a trap and getting a losing position out of the opening. Just my two cents.

@imakitty

I wasn't able to win a +2.5 because it required 10 ply calculation. I know I play trashy but a deep engine assisted repertoire will make me less trashy for 10 or so moves.

@GM01

"At low levels deep repertoires don't matter "
Yes, if you wanna stay in that low level for the rest of your life.

" Your first lesson is to read MCO. Your second lesson is to read it again " Fischer.

I know the principles. It doesn't make me able to exploit some strange moves which blunder a pawn after 15 moves or something.

P.S My Classical Rating is higher than both of you.

The last person to make a mistake loses. I'm going to give you an actually percentage like you asked for. 50%. 50% because they can either find the right moves or not. I'm going to start working on knowing at least 5 opening traps by heart by 2018.

@savagechess2k You might be right. But my point is that your opponents will probably take you out of your preparation and then if you were to get in a situation that required you to calculate 10 ply to get an advantage, you wouldn't have your studied theory to help you. Computer-assisted preparation wouldn't be bad, but keep in mind that your opponents will often play moves that are not the computer's recommendation.

P.S Your classical rating is only 70 points higher than mine.

wtf are you talking about? You are probably like 1400 fide you don't need to know any theory.
There are no holes in main lines. Everything is 0.00

If you play more real tournaments otb against decent competition you will experience that your openings are not the only problem. You will even lose positions which you wanted to have frantically.

That's the way it That's the way things go.

WHERE THE HELL WILL I PLAY OTB IN A CITY ORGANIZES 3 TOURNAMENTS IN 4 MONTHS ?

@candice33 I am 1266 FIDE and I need to know theory.
( But some of my lines have NO theory like Ulvestad or 4...Qh4 Scotch )

Computer assisted preparation is NOT only considering best moves. It's considering ALL logical moves and learning to exploit the ones which look logical.

@savagechess2k
If you're talking about opening repertoires with depths of 15ish moves: It's cool and fun to know an opening line that deep of course. And isn't this what we play for? Fun. So you're definitely doing it right if you do it in a way that you enjoy.
That said, I don't think it's worth to go that deep in terms of most effective preparation until you get in range of a title. The depths of my own repertoire, which took some months to create (all together at least a 3-digit number of hours), range from 5 to 9 moves, depending on frequency and sharpness of the positions. It's quite a beast - although I merely included opponent's moves that are favored by the majority in databases, my repertoire includes lines that I never had on the board. I noted the chance of occurrence for every position to keep track of if I'm in too deep already. I only included e4, d4, c4 and Nc3 as first moves of my opponent playing White and also never went deeper than 0.5 % of occurrence. So, obviously, a lot of fancy side lines are missing that can mess with me. But I don't feel it's necessary to prepare against this since chess is just a hobby (for me), and it's unlikely to happen if it's that rare. In other words, I happily get crushed with a fancy line when I get advantages early on in 5 other games with lines I prepared. If a played opening is part of my repertoire, I'm comfortable and save. And that's for a lot of my games in the first couple of moves.

TL;DR: About repertoire efficiency, I mainly recommend to have fun and go as deep or broad as you wish. You will remember/memorize the positions much easier that way. In general it may be better to go rather broad than deep though, especially on our level of play.