The infantry soldiers seem not to be marching in step with the drum, both when in column and in line (their steps are not synchronized).
Also infantry lines seem to break a bit when a line infantry unit approaches the enemy ("attack enemy unit"). Then they stop still at a significant distance and reform the line. While I understand that attacking columns could march at discretion when marching right to the enemy line for sake of speed, this was not standard practice for a line, which would usually march in step to keep the formation as much as possible during movement and maneuvering (after all, the line was a more clumsy formation than the column). At least this is what the drill manuals say.
Please correct me if I'm wrong.
Regards,
A. Grilo