You must stiffen your resolve on WIFI in schools ...
Its obvious some scared Henny-Penny's in the schools have influenced this Sir William or are playing to some "pet theories" he has.
The losers here are the students and the teachers. One of the primary benefits of wireless is that it can bring easy connectivity to older schools. Even when (expensively) re-wired - older schools still have fewer LAN taps per class room - and the LAN taps are not optimally placed.
This means teachers (who sometimes move to different rooms during the day) may not be able to easily access class notes stored on the server or connect their teaching laptop to both the network and the class projector.
Whereas wireless give all the flexibility of the newest schools that are wired to the hilt for connections. So until you Brits clear this up I'd say those poor lads-n-lasses at older schools are getting a "less rich" educational experience.
I work providing on-site support at a 2200 student high school built in 1959. Its been decently rewired - but we are adding 5 discrete wireless nodes to improve connectivity. We are building a new expansion wing next year that will be pre-wired for integrated wireless nodes.
As to ADHD - my step-son (born 1978) is profoundly ADHD ... I don't think we had wireless anything back then (in common use). Everything I learned about ADHD is that it is heavily hereditary and typically passed on by the father.