"I had to work on programming more carefully and think things through before diving in, or I’d have a hard time working in a large group." This pretty accurately describes what I went through before joining a larger organization. However sometimes larger companies train you into a mentality of working fast and letting QA sort it out, which isn't always the best thing.
After watching notch code a bit, I'd say that the way he dives in and works has been very successful for him. It's a different style but I don't think it's bad in of itself. I might definitely be bad when working in large groups, but that is not the only way to work.
I personally don't think working in a large group is particularly rewarding for a programmer.
It's easier to "dive in" when it's a short term project that you are working on alone and it's in a problem domain that you are familiar with (in notch's case games programming).
I'm at the point know where I can build an E-Commerce site in an MVC framework and implement Client & Admin Logins , Stock management , product search and a shopping cart without having to engage my brain because the structure to me is fairly obvious.
On the other hand if I had to design a game I would have to think long and hard about how the different components would fit together and even then I would most likely get it wrong somewhere.
