From my testing....
A Crash Course in Collison Detection!
Objects Speed Phase allows travel through:
Enemy targets
NPC targets
Friendly targets
Moving vehicles
Atlas Park Blimp
Paragon City Tram/Rail Car
Objects Speed Phase does not allow travel through:
Traffic Lights, Benches, Newspaper Stands, Light Poles, Bus Stops, cars, trees, fences (wooden and metal), ladders, dumpsters, fountains, information kiosks, rocks, bushes/shrubs, pallets, oil drums, shipping containers, City of Heroes pinball machine, forklift, blue box, desk, fire extinguisher, gargoyle, police cruiser, elevator doors, ferries, black market semi-truck, Mayhem or Safeguard Mission Vault door, any destructible objects in mayhem/safeguard missions, prisoner doors (oh man!), Blackline helicopters, Rikti mothership shield in RWZ/Echo: RCS, or the Rikti ships outside Pocket D,