I have a hybrid (leaning more towards a roadie) running 28mm tyres. Reading around forums etc, road bikes are geared (in both senses) to allow you to go further and faster. Would it be an improvement in a turn of speed if I was to go from 28 to 25 tyres? Would I be able to go further and faster for the same effort? Thinking about the Specialized All Condition Armadillos 25 (Currently Specialized Nimbus Armadillos).