What Mr Hoh is saying sounds very similar to what another experienced Afghan hand, Rory Stewart, is saying: we shouldn't abandon Afghanistan, but we should tone the military effort down, not scale it up.
I also think more centralization is bad for Afghanistan. Finding a way to wrest control from Karzai, so he can more easily improve his performance, and finding new Talibs and the as-yet non-Talib recruits to run provinces and villages, is key.
That same Economist blog is linked to a new .pdf report
I've not yet had a chance to read.