Comps...

Yes, there are divisions in ALL dance genres that are available in many large events.

Normally divided into 2 categ... American Style and Intern, Style .
In the states, they are even subdivided into " ability " levels within each dance .
The " english " system is comparable but as of yet, no Amer. style dances ( it is being taught here ) .
Now to Speed... it is a determining factor in this sense.. the " speeds " of dances in Amer. style , may sometimes ( at Bronze level ) be slightly faster.. F/Trot is a good e.g... the Silver level dances ( smooth ) follow closely those of the Intern. style .

The Intern latin and Amer. style Rhythm, is where we have a wider range of speeds .
Lastly, " speed " does in many cases determine the dance.. very fast waltz ( 54-58 bars p.m/ ) would be V.W. and fast Rumbas ( a generic term ) may become Guarachas and or mambo / Salsa.

The " styles " of dance have been impacted by their usage... social and or comp. Both co exist due to need and demand .

One could say, that " speed " became the Mother of invention for Dance evolution and style .
I have an article due to be published on the evolution of Mambo / Salsa . It may be on Salsa Forums shortly, and a couple of other sites.