I decided to define this phrase because the other day I heard someone mentioning it casually in conversation, I have recently been told that the phrase is common use in the Manchester area, UK.
So, I thought I would explain how this phrase 'actually' came about.
The act of doing something accidentally good or successful, extremely good luck, a fluke. Occurence based solely on luck or chance.
To perform or pull a jammy paul.
The phrase originates from the "Super Mario 64" video game, (it's a long story), whilst on Cool, Cool Mountain (Course 4), the "Big Penguin Race" level, my older brother's best friend named Paul Rowarth was 'sliding down the slope' (Nintendo fans may understand) when completely accidently and unintentionally fell off the slope, but with a stroke of luck somehow managed to 'fall' back onto the below track and continued sliding, to which we exclaimed 'Jammy Paul!', he then continued and completed the race in a record time, and when the penguin completed the race and approached him we expected him to call him a cheater etc. but to our surprise he congratulated him and surrendered his star.
I recently bought a 'Nintendo DS' and the remake of this game and found that they had corrested this error, I was quite disappointed.
"Hey guys, Dan pulled a jammy paul"
Mike - "I beat him at the game even though it was my first time!"
James - "It was probably just a jammy paul'