Partly Facetious: I never heard of minus two formula

"This minus two formula is simply beyond me."
"I never heard of a minus two formula, minus one yes..."
"That's because you target the head, once the head rolls life is extinguished..."
"Hmmm, not sure about that, take a snake if you cut off its head it does survive for a while...OK not days or hours but it does survive and..."
"Sounds like some political parties who lose their head and the replacement may not be as popular."
"Would you please leave Zardari sahib alone - he is an interim head and you know and I know that his heirs are his children, I mean he can't write a will giving control to his sister in case of his death."
"Hmmm, there is a minus Altaf bhai formula, then there is minus Zardari sahib formula and lately minus Nawaz Sharif formula though I haven't heard of a minus Khan formula yet. There was even a minus one in cricket, the British visa for Mohammad Amir was delayed and there was concern that..."
"You know getting a UK visa from Dubai for Pakistanis was the worst idea ever. I mean I know people who were rejected even when they had valid US visas, and need I add the US does the most vigorous scanning, and the reason: the visa officer sitting in Dubai does not get to see the passport and cannot ask questions and what is absolutely ridiculous is the failure of the visa form to ask for proof of financial information. If you are going to have a visa office in another country then surely there is a need to have a more comprehensive form requesting relevant information and..."
"I get it, let's do a tit for tat - let's make it mandatory for UK nationals to get Pakistani visas in...in...Putin's Russia or even Syria."
"Don't be facetious; the visa office was shifted for security reasons."
"And the US visa officers need less security?"
"Right, but that's not our decision, so what did you mean by minus two?"
"Oh, Chaudhry Nisar wants minus Khawaja Asif and minus Dar which is why one seat was left empty, the seat opposites the chief of army staff and..."
"I thought that was left empty for Nawaz Sharif."
"Don't be facetious."