No kidding. Drag reduction by the addition of polymers, the discovery of which is attributed to the british chemist B.A. Toms, became popular knowledge by about 1948.
Toms's effect has been reported as being applied, for example, in the Alaskan oil pipeline, in enhanced oil recovery, in firefighting, and in various military uses.
Nowadays, the principle is being studied in medicine to reduce drag in blood vesels by injection of polysaccharides.
One theory -among others- trying to explain the phenomenon says that the length of the polymer molecule is related to the microturbulent eddies in liquids, keeping waves from propagating from the eddies, thereby reducing turbulence.
Those of you involved in hydraulics may be able to add info. for our own education.