[quote=@Agent Orange]
Both, I guess. Like you said, there's some stuff here and there in your posts and others - run-on's, repeating certain words, purple prose - that people tend not to see until they're pointed out. There's a lot of stuff in my writing I didn't catch until an editor called me on it (and who keeps calling me on it) and there's probably stuff I'm still not seeing. Like the fact I wrote stuff three times (four times including the last).
[/quote]

I would personally approach as if someone asks for critique, go for it or if something is preventing your comprehension of the post. Otherwise most of what you mention above is just nitpicking and unless asked to be corrected will potentially upset and drive away writers. Most people on the Guild even in advanced are doing this for fun or as a hobby.