Starting out I was told double it and move up a unit.

2hrs === 4 days.

A week == 2mths.

Anything past that would never get done.

He was a cynical bastard but not a bad guy and sadly he was in a lot of dysfunctional environments not that far of the mark.

Why add 20%? That's upside precision for something so inaccurate. 2.2x is a good way to set a budget for someone doing a task after it's already been done once by someone else.

The golden rule of estimating is to measure past estimates and use them as a multiplier in future.

The platinum rule is to stop estimating because it's useless.

Double it, then add 20% make a 2.4 modifier.

  20*2*1.2 = 48  
  20*2.2 = 44 // I, also, was confused myself at this point  
  2 *1.2 = 2.4 // not 2.2

Right. Estimating before you even know what you _don't_ know is tea leaf reading. It's better to ask the person who wants it done "how much is this worth to you", or "what's my budget to get this done", and then work from there.

The golden rule of estimation is to give a 1-10 confidence level and if your confidence level is below a threshold (7-8 for example) then also define the risks. Finally, use that analysis to give a reasonable upper and lower bound (or be honest and say "I don't know).