The cost of a look-ahead bug

Closing prices on consecutive days are $100$, $103$, $101$, $104$, $106$. An honest rule is flat over the first move, then holds $+1$ over a move if the previous move was up and $-1$ if it was down. A buggy version uses the sign of the move it is about to hold, for all $4$ moves. By how much does the buggy total profit exceed the honest total profit? Ignore costs. Give a whole number.

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