The party I was most interest to talk with, those promoting the double length northern runway seem to have gone into receive only mode since the consultation ended, hence my request for opinions here.
I can't say I'm surprised.
The split-runway proposal served a useful role as a makeweight, in order to pad out the Airport Commission's shortlist from 2 to 3 candidates, but without a snowball's chance of being adopted (as the airport owner has made clear to the Commission).
So the promoter's work is now done.
If you're interested in opinions on the proposal, there's a ton of debate about it over in the Airlines, Airports and Routes Forum, both in the main Heathrow thread (from December 2013 onwards) and in this one:
http://www.pprune.org/airlines-airpo...twick-2-a.html
And if you PM me, I can put you in touch with the with the guy - a former Eastern Airlines pilot - who first patented the split runway scheme.