A thread today got me thinking about this. A new thread pops up with an interesting title. You read the OP and you have an answer to his question, a witty response, you want to correct his grammar, etc... What do you do?
I first log into my troll account. Then immediately rate the thread with one star, leave an anonymous hate message in the OP's rep, then begin searching for a .gif or meme that will hurt the OP's feelings. Finally, I log back into this account and attempt to add value to the thread. Rinse and repeat.
Generally, I read the whole thing before saying anything. Some threads are too long to do that for though. When I want to participate in some behemoth, I'll read the first page to learn the orgin and then the most recent 2-3 pages to see where the conversation has turned and then post.
I'm usually on cfans often enough that I can read an entire thread before responding. The Lin vs. Lillard thread is an exception, shi* blew up fast
Interesting thread topic. JV nails it for me. I rarely post in GARM because (a) more often than not someone has already stated my feelings on a topic and (b) I use it primarily for Rocket news, rather than conjecture. Other forums are similar. In D&D I shamefully resort primarily to snark because everyone is pretty entrenched and tweaking each other is better than flinging actual poo.
Usually, I read the whole thread before saying anything. Some are too long to do that though. When I want to participate in some epically long one, I'll read the first page to learn the topic and then the most recent few pages to see where the conversation has gone and then type out a post and usually delete it.
For the most part, I peruse the thread in its entirety in preparation to saying anything. A few have too many pages to do that. At the moment I would like to add something in some extremely lengthy thread, I'll skim the first page to feel abreast about the subject at hand and then the most recent few pages to hopefully determine where people have taken a turn and then type out a post and usually copy and wait to paste it.
No need to read contents of thread before posting far-reaching references to Vacation, Animal House, Airplane, etc.
Either some people are not being honest or the people who fall into the third choice aren't reading this thread.
Since my opinion is more important that everyone else's, I just read the OP and give my take, screw the rest. DD j/k -- I read as much as consumable usually looking for a post that I'd like to engage. Someone has likely already posted a similar take to mine, so I like to find those and expand on their take. Or, if there's a post that is egregiously opposite my take, I'll debate that. Lately though, I prefer not to and just let it slide and look for posts similar to my take. Disagreeing can be fun, but agreeing with others builds internet friends who will respond back in other threads to your take.