Often used in reference to ones ability to cause destruction to toilet cubicles, by means of mass-urination across all surfaces.
This behavioural act is most-often undertaken by frustrated commuters on packed trains, and renders the toilet cubical unusable by others. By creating inconvenience and raising misery to fellow travellers, this (relatively speaking), causes a reduction in their own misery, and makes them (effectively) happier. This form of relativity was never published by Einstein, but most likely, was at the forefront of his theories and was the catalyst for his greatest thoughts.
Adverse effects may be encountered when, after participating in MPS, you find yourself in a position where you need to re-use the toilet, being forced to stand in pools of your own piss.
Veteran MPS users may hone their skills to almost god-like levels, and undertake advanced techniques such as urinating only upon the toilet-roll. Unsuspecting subsequent users of the toilet will, on initial inspection, consider the cubical clean and will proceed to engage in defecation. Only on completing this act and requiring to wipe faeces residue from their crack, will they find the toilet-paper unusable.
Ted: "I destroyed the toilet"
Petey: "Holy shit. MPS, man!"
Petey: " Fuck, I need a piss, but Ted ruined the toilet with his MPS"
These women believe they are princesses who deserve special treatment because they own a vagina.
Tommy: Man, fuck MPS and all it's schools.
Remmy: Why are you dissing MPS?
Tom and Bob: Cuz Remmy, MPS sucks and its the worst district in Wisconsin.