Are Tanks Canon?

[akita-ken 581]

Aw yeah, tanks are canon all right

 

Ok, maybe headcanon. Still, MLP does reference technology that would seem awkward in that environment. (Remember Con Mane and the laser security system for the MMMM cake? My guess is, technology is injected by the writers whenever convenient They don't have to explain how it got invented anyway 

[Sunny Fox 5,939]

It's a water tank, in both cases. Water tanks are large and ungainly, which is what Rarity tried to avoid in making Dashie's dress, and went a water tank comes loose from it's moorings and rolls down a hill, it's pretty unstoppable. Dashie must have seen one fall when she was younger, and it left a deep impression on her.