I've figured its about self-esteem. Would you ever cut someone off remorselessly if you were riding a chopper? no. Would you ever run a red light when everyone is being civil and waiting their turn if you were riding a Kawasaki Ninja 650 R? no. Would you ever overtake another motorcyclist going at 30 by hogging the high speed lane while going at 32 yourself if you were riding a Harley Davidson classic Fatboy? no. NO! NO! NO!
Why you wouldn't be a meanie on the road while driving a better set of wheels is that you'd actually care what people thought of you. You'd have self esteem. You'd have respect for yourself in your own eyes; and THAT is what the cd70 walas lack. While sitting on that horrible 4-stroke engine, they feel so worthless, lives so meaningless, ride so ugly, existence so sad.
So the theorem simply clarifies that they're not bad people, they just made a bad choice when they stepped into the wrong Honda showroom.