It will be interesting to see how this works out.
The general opinion in the transit field seems to be that double deckers are slower to load and unload than articulated busses. Even London has been migrating to artics. But maybe in a crowded city, a smaller (in terms of its footprint) and more nimble vehicle would have an easier time getting through traffic.
I will be posting my evaluation of transit in Switzerland, and what can be learned from it, in this blog soon--meanwhile, if you're curious, you can read about my trip from a more purely tramfannic perspective over at nkncat.blogspot.com.