It's 'whether' not 'wheather' in that context, artic.....
As for dyslexia...I've met several people with genuine dyslexia, and it's a bit different to the way most 'dyslexics' post on here. Usually, you get the right letters, but not neccessarily in the right order, to paraphrase Eric Morecambe.
I don't have a problem with genuinely poor spelling, as long as I can work out what the poster is trying to say. I do have a problem with lazy writing though. Hence my total support of the ban on text-speak.