It means discarding both technical and fundamental analysis. Instead, you enter a position when your scalp itches. That is, the signal to enter is when you scratch. This is an incomplete system, as it doesn't tell you when to exit.
i read it here http://www.futex.co.uk/about/paolo-rossi-founder/ Paolo sought techniques to 'hand pick' new talent and teach them to trade from scratch.
"Paolo sought techniques to 'hand pick' new talent and teach them to trade from scratch." In that sentence he is using cryptic terms, he might be a Mason What he means is he taught them to trade using a black cat for good luck (scratch is another term for a black cat)
PS: Pulling your leg. Trading from Scratch means trading from nothing, or in this instance beginning from having no experience. It's an English (UK) terminology. Starting from the start line with nil experience and then grooming new traders without previous pre-conceived trading biases or assumptions that may have been false.