I agree, which is why, I suspect, we won't get very far with the issue of the dyslexia spectrum until we can map problems to specific causes, at which time it might be possible to say to pushy parents "Brian isn't dyslexic, he's an obnoxious lazy brat with clingy, over-attentive parents".

I do, though, think that it needs to be emphasised that dyslexia isn't a condition, but a spectrum of issues. For example, my nephew was "diagnosed" by an educational psych as dyslexic, but the actual problem he suffered from (words moving and shimmering on the page) was solved by colour-tinted specs. Within a month of being prescribed them, his reading age had jumped 2 years. My g-dson however, also diagnosed dyslexic and statemented, has no problem reading, but is still unable to write coherently even though he's in his teens (reversed letters, bad word order, handwriting style of a toddler etc) but can type his thoughts perfectly well.
It's a puzzle.