Someone who has ADD wouldn't be as good as he is at fighting.
Youd be surprised actually, the hyperactivity aspect has its benefits. I suffer attention deficit, hyperactivity and with it stress related anxiety.
I struggle to sit still, constant fidgeting, say im watching someone perform on stage, i struggle to focus, struggle to pay attention, weird thing is, when it comes my time to perform (i play a little), its like i enter a totally different place, anxiety lifts, and a sort of weird calm comes over me and I can perform fine. Thats the weird thing about mental health issues.
Similar, say, sitting at home, doing nothing, i can suddenly get ridiculous loss of focus, anxiety, panic and crazy levels of stress over something as simple as not being able to find the tv remote, yet if something really serious happens, say someone is injured, i can suddenly be the least stressed, calmest, most focussed person there who can deal with the situation.
Its like my brain is constantly looking for something to do, constantly switching attention from one thing to another, and finding things to get stressed, or excited about, when you give it something, the right thing, it can control it really well. For me its being out on the bike riding. Complete and utter calm
Thats the funny thing with mental issues, if you find the right channel, you can actually perform in a totally different way to what would be expected.
Nick Diaz would be a good example of someone who manages to fight just fine.
In some ways I think it could actually help. One benefit of it is i can watch tv, read sherdog, post on twitter, have a conversation with someone on the phone, all at the same time without missing a single thing. People will talk to me thinking im not paying attention because im doing ten things at once, yet i can repeat back what they say word for word.
That has its downsides, in a shopping centre or busy pub, station etc there are so many different noises, loads of conversations, chatter, tannoys, my brain tries to take in everything and obviously it cant which leads to confusion, panic etc, but the upside, that ability to process multiple pieces of information at once, that sort of heightened senses, could actually in MMA be a huge benefit. If you can channel it right, heightened awareness could be a huge plus.