This is extremely disruptive as usually when pasting you place the pointer exactly where you want the Paste to locate.
Now whenever you Paste, you have to clean up the result.
This is especially unwelcome if trying to do a methodical step by step critique or support on a quote. Every time you paste in the username part OR the /quote tag, you have to go over it and clear it up.
But it can also apply to re-using a technical phrase, or quoting without using the post quote, or to moving a line or phrase to a different location in the post. The last one is probably the most common.
Could we lose the newline before and after Paste please.