Front brake on the left is a convention from road bike brake setups. Shimano and Campagnolo road bike brakes are designed for the cable routing from the rear brake to go down the left hand side of the frame, and flow neatly, across the headtube and into the right hand lever, and the cable enters the front brake on the left hand side and crosses over neatly with a nice flowing cabe line into the left lever, giving really nice flowing cable lines. A lot of British road cyclists use their brakes the 'continental' way, for this reason. Front brake on the right was introduced by some British road cyclists, from 'back in the day', when brakes were shite, because most people are right handed, and the majority of the braking power on a conventional bike comes from the front wheel. It kindof stuck in this country, but not really anywhere else!