Originally Posted by
pibach
yes, the single piece main tube design of the swift might be stiffer. And if you have a very strong stroke, the flex of the Mu frame can absorb some energy. But this won't be much.
As Sheldon Brown pointed out, the issue of frame flex 'absorbing' energy is a red herring: the energy does not get absorbed, it is fed back into the drive system as the flexed bit straightens out again (mechanical memory and all that, otherwise the frame part concerned would become permanently bent).