I know threads can sometimes move very quickly, and that people want to respond to particular posts as they come across them...
However, when people are replying directly to the OP - especially when they haven't even read all the OP's posts - with what they must surely realise is going to be an obvious and far from original response, I do wonder what they think they're achieving.
Even when I have read the thread, if somebody has said what I would have said, I accept that it's been said and I don't duplicate it.
When questioned, people will cite the fact that they consider the thread too long for them to read, but they apparently don't realise that, by adding their (much duplicated) comment, they're making it even longer for everybody else to read. Maybe they just assume that their time is much more important than everybody else's?
I do wonder how many of the people who wade right in obliviously would do this in real life too: turn up halfway through a discussion and just chime in with their thoughts and wisdom on what they assume it must be all about?
I'm reminded of the Gavin & Stacey thread at Christmas, where somebody said they'd watched a compilation of '20 best G&S moments' - obviously intended as a highlight/summing up nostalgia trip for people who are familiar with the programme - and found it rubbish as they didn't know any of the background or any of the in-jokes that had developed over the years!
By the way, even if your device doesn't allow 'see all', doesn't it still highlight the OP's posts on a different colour, so you can fast-scroll through until you get to a green/pink or whatever post?