I would be surprised if part of Milan's plan wasn't just to paint some bits of roads a different colour and call it a cycle path. These large initiatives tend to be a mix of solutions, from paint to dedicated cycle paths. This has happened pretty much anywhere a city has announced upgraded cycling infrastructure. Some cities ratio it better than others.
As they did last year... There was quite some adapting for the drivers then and still confusing for drivers not familiar with these streets. Newly painted lanes with width that would vary every 50-100 meters (or less), random taxi/bus stops and parking being interchanged with the bike lane... Not easy for the riders nor the drivers...
