First, I also had trouble with XCode. About the regex in vi: there is a technique of writing/maintaining code based on substitutions instead of inserting/deleting. It can be very powerful but you have to "write" your code thinking about the patterns and maintaining some kind of structure. I am not saying that it is good or recommended. It's interesting. I coded for like 5 years like that. I was maintaining a codebase completely solo. When working with a not very synchronized team or having tools like resharp or omnisharp etc avaliable, I don't think it would pay off.