I doubt the cycle tracks proposed would trap cyclists in a door zone. The couple that I've ridden around here (Boston) that have already been installed don't do that, even when they're between the parked cars and the sidewalk. The one I ride regularly has the parked cars, a cross-hatched sort of void area, then a very wide bike lane, then the sidewalk. And it's one way, so even when people are cycling next to each other or passing one another, there's still plenty of room to avoid the door zone. The rest of the cycle tracks I've seen around here aren't near parked cars at all, but take over some of the sidewalk real estate.