+1. Team Miyata, but it's a 1982 model. Correct build is Dura-Ace EX with the Dyna-Drive crankset and pedals.

Dyna -Drive is actually a reference to the pedals. On typical pedals, the top of the cage is above the axis of the pedal spindle, which causes an unstable platform. Dyna-Drive lowers the top of the cage, so that it coincides with the axle's axis, proving a stable platform. Reportedly, the cyclist expends energy trying to maintain stability in a normal pedal, while the Dyna-Drive's inherently stability allows the rider to divert this energy towards forward motion.

The downside is that the axle can no longer run beneath the whole width of the pedal to bear the load. The axle and bearings must be located entirely inboard of the cage. To accomplish this and avoid widening the spacing between pedals (Q-factor) Shimano employed an oversize (1") axle that allowed the bearings to located within the plane of the crankarm. The crankarm itself had no innovations other than the 1" x 24TPI oversize hole, though it was one of the stiffest cranksets availble during the era.

While I can't comment on the energy saving aspects, I can testify to the extreme stability of the pedals, having had them on a Dura-Ace AX group. Alexi Grewal regarded them highly and used them on his 1984 Olympic winning Pinarello, in spite of SunTour sponsorship.