Perhaps they were, but the general rule was exactly as I said, if you wanted something different than what was available then you were SOL.
The example I was going for was the Tatra T3, which is the most numerous tram car ever built, with over 14000 pieces built from 1960-1989. It also happens that it underwent no technological innovation in that time period, despite many transit agencies in the Eastern Bloc wanting something that was more energy efficient rather than the vehicle's former control system, based off the PCC design. If they wanted more energy efficient equipment, they would have to procure it and install it themselves, sometimes in brand new tram cars fresh from the factory.
It sounds to me like this is what "cplchanb" is insinuating is the case, that Metrolinx appear to have had no recourse against architects with pie in the sky fantasies. Which is, of course, bunk. Don't blame the architects, blame Metrolinx for not being able to properly spec their project.