As the tyres wear, the rolling circumferance reduces. What effect does this have on?
a) acceleration - i am assuming that it will be quicker to accelerate
b) top speed - assuming lower
c) recorded power output on dyno rollers (cant get this straight in my mind at all)
sorry but up early and woke up with this in my head

An average tyre with 8mm of tread at the start of its life will have a rolling circum of almost 38mm less when down to 2mm tread.... surely this must have some impact as it is quite a large amount.