well they used the 'attack column'
also more from a counter argument against Sir Charles Oman (wikipedia)
"During the early stages of the French Revolutionary Wars, battalions in French armies often attacked in column formation in an attempt to drive through enemy lines by sheer weight of numbers. Against enemy units already weakened by the fire from skirmishers or artillery, this was often successful. Later, during the Napoleonic Wars, French units would approach in column formation and deploy into line when close to the enemy. However, against the British they frequently failed to deploy into line before being engaged. During the Peninsular War, after the Battle of Sabugal (3 April 1811), the Duke of Wellington wrote, "our loss is much less than one would have supposed possible, scarcely 200 men... really these attacks against our lines with columns of men are contemptible." These failings were still evident at the Battle of Waterloo in 1815, prompting Wellington to comment, "They came on in the same old way and we defeated them in the same old way."[4][5]
The military historian James R. Arnold argues that all armies of the period used column formations at times on the battlefield; the military historian Sir Charles Oman is credited with developing the theory that the French practically always attacked in heavy columns, and it is only now that this alleged error, propagated by other British and American authors, is being repudiated.
the problem was timing, and being volleyed while in formation change, which was not done on the fly but stopped.
http://napolun.com/mirror/napoleonistyka.atspace.com/infantry_tactics_4.htmHowever every commander had leeway as to what formations to attack in from Napoleon himself.
d'Erlon decided to form colonne serre which caused even worse casualties in men a bad case of
morale drop...imagine men marching almost running with their heads bowed down .
Napoleon and his Marshals/Generals had very little consideration for the infantrymen even though
all adored Napoleon and would have died for him ...and they did.
Wellington upperclass standoffish attitude towards the lower class: his infantry did the very opposite, he spared them
a lot of grief by choosing to defend always on terrain which would offer cover for them.