i think you make a good point regarding the lessons- if you aren't careful, they can turn it into work, rather than play/fun.
I've never had guitar lessons- though I wouldn't suggest having no lessons if you've never had any instruction in anything musical (I've had piano and drum lessons, so at least I have a fair idea if i'm on the right track or not)- and I practise guitar way more than I ever practised piano or drums. to be fair- I probably like guitar more. But even still, there is something to be said for that.
That being said, I still don't practise enough. And I probably would have picked some things up a bit quicker had I had lessons.
But it's definitely very important getting someone who teaches you the things you want and in the way you want to learn (within reason). Some teachers (and i say this as someone who is incredibly biased in favour of teachers, if anything- both my parents were (not music) teachers) are very, very annoying. They have a very particular way of learning and teaching, and if you're not willing to learn in that way, they'll go out of their way to prove your way wrong and make it difficult for you. Even though there are umpteen ways to learn things. A similar, related problem is the type of teacher who forces you to learn boring scales and the like, on the principle of "weeding out" those who aren't interested. That's BS of the highest order, if you ask me. If you make something artificially boring, you're going to weed out good students.
Of course, if you get a good teacher, it'll help your playing like nothing else. Just in case it looks like i'm warning you against getting lessons, because I'm really not.
I'm also sure you're nowhere near as bad as you say you are. :)
