What I meant was if you unscrew the cleat, put the washers on the screws between the cleat and the shoe (assuming the screws are long enough), thus raising the shoe from the pedal by 2.5mm. This, hopefully, would approximate a crank that is 2.5mm shorter - maybe.
TBH, by the time we've argued this through, the OP will have got himself a new crank :-)
What I meant was if you unscrew the cleat, put the washers on the screws between the cleat and the shoe (assuming the screws are long enough), thus raising the shoe from the pedal by 2.5mm. This, hopefully, would approximate a crank that is 2.5mm shorter - maybe.
TBH, by the time we've argued this through, the OP will have got himself a new crank :-)