Were the 'Tranados' ever supplied by one manufacturer?

Technically, no. In reality, yes. By the end, only the Marstrom was deemed worthy by the competitors.

I think the Brits used a Grahm Eccles built boat that they thought was a bit better then Marstrom and would measure into the templates. ISAF forced a measurement standard on the masts though, which became SMOD for the cycle for competitive and economic reasons.

Flexibility in the class rules (Tornado) will lead to development and money spent... thus pricing the class out of the reach of many. SMOD changes the game from develop what you want...to find what you want in the production run.

(All of those old ISAF goats that Luiz just blasted get to study each boats class rules and figure out what the loopholes are... and what will have to be changed for ISAF to make it olympic .... Sounds like fun to me)

It is fun! It just happens to give an edge to the richer/smarter MNAs while less developed MNAs have a perfect excuse to spend other people's (or government) money to send useless politicians to the venue.

Again Luiz has nailed it.