It is not my "inability".  It is my lack of desire to waste time on being succinct.  I can be, but it takes time and effort I don't want to spend on a forum.  I already spend too much time on it, I cannot spend 2 or 3 times more.  I don't want to be "read".  I don't want to tell the world.  I want to find out if my thinking is correct, if there are intelligent counter arguments to my thinking.  For that, I want to give all elements that led to my argument.  That takes room.  It would take less room if I reworked it, but that's too much of an effort.  If someone doesn't have the attention span to read me, he probably won't be able to give me a counter argument either that is valuable to me.  I may of course push off the true expert that could point out an error by the walls of text I produce.  But a true expert may not be put off to read a page of text.  But the casual reader that is put off by long arguments, won't be useful to me, so I don't care he doesn't read.  

I certainly don't want to blog, because I have nothing to "tell the world", and certainly not for free.  I want to learn from the world.  My walls of text, spread all over the place in a disorganized fashion will also make it essentially impossible to steal anything useful from it, if ever I decided to sell something of it.