Perhaps, to have a quick check I tried a battle on Heart Gold. The B/W battle lasted around 1.10, having 4 moves each. In the same time against Will each side managed around 2-3 each, and included in that time was with the time it took for a level 55 'mons health to run out and three Pokémon replaced.
I thought the levelling was unfair, so decided to boot up Platinum and try lower level 'mon. In around 1.03 each Pokémon had performed around 5-6 moves each, two of which were Growls. This was between a Lv. 4 Starly and a Lv. 2 Bidoof.