Well, I was not saying about a short post like a paragraph or two, but posts like the one I tried to answer, @lukestokes post, he is considering it short, but it is not that short.
I'm just gonna upvote this because of pity or something - I have done this too with long posts sometimes, but I don't think that I will do it again. If the post does not bring useful information, then it should not get visibility from upvotes, it won't be fair for others who work a lot at their posts and also bring original information.
I like that you admit sincerely that you don't read some long posts entirely, I am ashamed to admit and say this to others, even if I do it sometimes. I still have to work on my courage :)
This is one of my strongest and aslo weakest feature. I alway say my opinion honestly, even if sometimes I shouldn't. :'D