When working on different lengths and pivot points of the horse's leg linkage geometric simulations were drawn placing either pencil either marker at the tip of the foot of linkage mechanism.
During the simulation - different lines were drawn, which were not either symmetrical or even top line was too long. Top line is representing horses foot which has to move up during other legs are crawling the bottom path on the ground. What we were searching was relatively long bottom line and relatively short triangle for the top line.
At the end of tests, a path is made by combining two linkage movements: one with basic construction of linkage (support linkage at sides), while the other is inner loose linkage. Tests were made as a trace on a paper, but we can presume a real test would show weakness on the tip of the foot.
Final linkage's path