The whole point of this competition is compromise, and picking the compromises that lead to a car that will gain the most points. Anyone can design a car/accumulator/electric drive system to do only 1 thing really well (accel, auto-x, endurance, etc), but the trick is designing one that can do it all better than everyone else.
I will agree with you that compromise is key to winning this as well as any design competition; to do the best you can, with the time you have, and the resources you got requires compromise. But compromise is a method of wining the competition not the point of it. The point and purpose of the competition as stated on the formula hybrid official site is as follows,
Formula Hybrid™ is a design and engineering challenge for undergraduate and graduate college and university students. They must design, build, and compete an open-wheel, single-seat, electric or plug-in hybrid-electric racecar. This car must conform to a formula which emphasizes drive train innovation and fuel efficiency in a high-performance application.
1. To give engineering students the opportunity to work across disciplinary boundaries while engineering and developing an electric or hybrid-electric race car.
2. To encourage and promote the development of high-efficiency automotive drive trains.
I don't bring this up as a means to argue about what the point of competition is but to state that the originally proposed question concerning swapping accumulators has some validity in the context of this competition's purpose.
The original question came about after running across an electric car company proposing a battery (accumulator) swapping design rather than the current plug-in design. The idea behind this is that one could drive their vehicle till the batteries start to run low, then pull in to a swapping station and change them out for fully charged ones, nearly as fast as filling up a gas tank. With that, who is to say that they couldn't have different performance levels on their accumulators to accommodate different driving styles/conditions/distances/etc.
Furthermore, at the competition any team can fill their tank up between driver heats for any event, having a spare accumulator, even if its the exact same size, spec, everything, and passed through electrical technical inspection, why not allow teams to swap them out?