Were they really identical? It's very clear from the video that the trajectories of both serves before they hit the ground were not the same. Different spins result in different trajectories in the air and different speeds after the bounce.Oh so 18-19 year old Federer was struggling to win Wimbledon's because the court was too fast, and then on the slow court he lost in the first round the first year and then what had to change for him to win it in 2003? You're a funny funny guy.
Also, were the humidity and temperature the same in both finals? Those also have a huge effect on the speed of the balls and are outside the control of tournament organizers.