I will go against the general mindset I see in agility these days (not everyone, for sure, but a lot of people) and say loud and proud that it is okay to not train weaves using 2x2 if they aren't working for you. Seriously.
I've seen dogs with killer weaves trained with 2x2. I've seen dogs will killer weaves trained with channels. And shaping. And weave-o-matics. One of the most reliable weaving dogs (and a toy dog to boot) that I train with was trained using gates like Cali described. 2x2 works, but so do other methods. And I believe just about any dog can be trained with all of those methods, so you need to find what works for YOU.
I can't train with 2x2. I tried. I went to a seminar. I watched the DVD and took notes and read the articles and holy hell my brain does not work that way. It just isn't for me, and Gusto was getting even more frustrated.
I shaped my weaves. That's how my brain works, plus I have a dog who is a genius at shaping. And people make me feel guilty (granted, not a hard thing) for not having trained with 2x2.
I was having a long talk this weekend with a good friend, who is a brilliant trainer, and one thing that came up was 2x2 training. She actually mentioned that there is a "modified" 2x2 method by Mary Ellen Barry that she found much easier to work with. The article is free on Clean Run's website; I actually keep meaning to go look at it.