Well that depends on what you mean by readability, you (I) have to put in a lot more effort to understand some arguments, but since people usually refer to other posts it's often possible to follow someones reasoning to a greater degree in comparison to other forums/blogs I have encountered. But doesn't that go for native English speakers as well?

I think expressing yourself in proper LW-lingo is a bigger problem for non-native English speakers than actually fully grasp the arguments. Edit: That might go without saying, writing a good book is harder than reading one.