When I come across a users post that have trim quoted and added a hyperlink to the quote, I see them as a very good quality poster. What’s the essence of quoting a whole context when you just want to reply to a few comment of the user out of the many he has posted? No need of that.
Trim quoting and giving reply to only the part you wish to answer is a good habit of a quality poster and makes your post history also looks organized and not look like a cluster of unnecessary posts when viewed. The hyperlink added can always lead you back to the main post when you want to read the full text of the post.