The bars were dedicated to measure of the athlete because there was no other chance to adjust reach, cockpit length and bar-2-sadle vertical elevation. On the left side of the bar underneath the bar tape there is often the name of the rider engraved, in this case Thomas Barth. 

Here are two bars with different elevation and one is bend backwards to reduce the cockpit length. 
This design is based on 28” front and rear wheels and optimized the drag of the rider only. The second generation has a significant shorter wheel base and smaller 24” or 26” front wheel to get a aerodynamic advantage in team pursuit competition, by simply stacking the bodies closer together. 
The GDR frames were unmistakably to distinguish by the absence of a upper head set cup which was here integrated into the head tube and closed by a plastic cap, which often did not fit for smaller frame sizes because the steerer tube was to much extended out of the head tube . The Russians copied the design but used a regular head set. 
A frame joints were filled brazed, and all 3 main frame tube are oval, with a round seat post.