Why do I forget the openings so easily?

Because you don't use Chess Position Trainer or Lucas Chess to study them and you don't know why the moves that are mainline are the mainline.

http://omgchess.blogspot.com/2015/08/learning-openings-thoroughly-with-lucas.html

http://omgchess.blogspot.com/2015/08/more-on-learning-openings.html

X_PLAYER_J_X, I would expect someone like you to know all of that, with how basic it is, but when you look at the OP, it sounds like he's clearly trying to memorize and not actually understand what he's learning, and those questions I put on the Ruy Lopez are the perfect questions to ask someone who has a bad habit of memorizing and not actually understanding.

And the absolute worst opening for a pure memorizer?  The King's Indian Defense!  You will not believe how many players I've had play ...f5 against me back in the hey day when I played the Four Pawns Attack.  Playing ...f5 against the FPA is instant suicide, but hey, they "memorized" 20 moves of Classical King's Indian, and have no clue what to do when White plays the Fianchetto, Saemisch, FPA, Averbakh, etc.

The Ruy Lopez is the simplest opening to use to explain the concept of "how to study openings", not just deciding what opening and memorizing it like you were getting ready to take a 50 Question multiple choice US History test in highschool.

Not necessarily.  You can remember the ideas and plans so you can punish a move not in the opening's spirit.  

Yeah they are some gutsy basters playing f5 against the 4 pawn attack.

I even think playing e5 is gutsy lol.

I have always played c5 going for a Benoni type of position.

Do you still play the 4 pawn attack against KID?

I have lately been playing g3 systems.

I think black is crushed in them. I struggle with the black side of those systems. Its funny because the move g3 is not even threating lol.

Its like a passive system yet I struggle with black against it lol.

I started playing the Gruenfeld against it. I found no other response in the KID.

ThrillerFan wrote:

"... when you look at the OP, it sounds like he's clearly trying to memorize and not actually understand what he's learning, and those questions I put on the Ruy Lopez are the perfect questions to ask someone who has a bad habit of memorizing and not actually understanding. ..."

I think that there is a good point to be made here, but when you write things like, "If you are 'forgetting' openings, you aren't learning them properly in the first place", it makes it sound as if it is entirely the person's bad judgment. I, of course, am not in a position to know, but I suspect that the forgetful person was working from a book that was not well-suited for a person at that level. For someone near the start of chess adventures, it is not so easy to identify the right sort of material to try to read.

Also, isn't opening preparation something of a compromise between understanding and memory? In 2003, FM Steve Giddins wrote about playing openings that "are based more on understanding", but he did not refer to playing based ENTIRELY on understanding.

Anyway, thanks for all that Ruy Lopez explanation.