Except it forces me to slow down to "decypher" the text and makes the reading labored. I understand the point as it is part of the character, but it is easier to understand someone speaking in that vernacular vs reading the forced misspellings. I definitely don't want to get to the point of being good at reading it though. I wonder if this is how second grade teachers feel reading the class' schoolwork?

That's true. I'm sure Twain and Banks were aware of this, though. Apparently they considered the immersion to be worth a little extra work on the part of the reader. Whether the reader agrees is a different story.

I try to limit my use of it to just enough for my accent and way of talking to bleed through. I don't go for full-on phonetics, but I'm often "droppin' my g's and usin' lotsa regional sayin's." It probably helps that the people I text have the same accent I do, though.