It’s a stylistic preference. I usually don’t bother quoting the entire post (as is the case here). I just copy the relevant portion I’m commenting on. I personally dislike seeing threads that are full of posts that just repeat other posts and then add one additional line. I prefer posts that are new text with as minimal an amount of quoted text as is necessary to establish the context.
This was covered in detail in a doc I just saw from Netflix (and its deleted scenes extras) “this film is not yet rated”. Highly recommended.
Professionally speaking, I can confirm that he who pays for the movie to be made, and distributed, gets to decide what movie is made and distributed. Money talks. People like Mel Gibson can make movies like Passion of the Christ because people like Mel Gibson pay for movies like that out of their own pockets.
Continuing this hijack, there is one consequence of doing this. More than once, someone has quoted me and asked a question, but removed the attribution in some manner. This has resulted in me missing the question until it’s far too late to answer. I suppose, in the grand scheme of things, that’s not too big a deal, of course.
It depends: do you have final cut authority? 
I agree with this wholeheartedly. My preference is to quote with attribution and then delete all non-relevant portions. It really takes no longer (you highlight and copy the relevant portion, I highlight and delete the non-relevant portion) and, as Cerowyn said, it makes it easier on everyone else.
Yeah, well, this is also true. Nevermind, Little Nemo. 
I typically attribute the first post I quote from someone, then any subsequent quotes from the same person I do not attribute. If I interleave another quote from someone else, then I will attribute both quotes.
The idea is to be clear that I’m quoting and who I am quoting, not to post the person’s name repeatedly.
Also, I do not like the auto-formating of the quote= tag. It forces italics. Since many people use italics in their posts for visual cueing, it is frustrating to quote something and desiring the formatting of the quoted text to remain the same, and the auto function to force italics over it.
But I do try to bold poster names. I do that to help visually stand out on the page and because many poster names are not readily identifiable as names.
Speaking of director’s cuts. I don’t mean to hijack the thread (someone please let me know if you think I am) in a somewhat related topic, I recall reading some years ago that if a director did not like the film, he/she could replace their name in the credits with some other name. It was one name that was always used in this case, but I can’t remember the name, nor can I find any reference to this practice. Anybody have any information about this or did I just dream it?
Thanks KneadToKnow. I knew I didn’t dream that up. I also searched Wikipedia but apparently I was using the wrong search criteria.
Alan Smithee.
It’s no longer used, though, since now everybody knows what the deal is with Alan Smithee. The DGA will instead make up a random name to use once for each case.