G'Day Hans - Karl
"La division marchait la gauche en tête; le régiment formait le tête de colonne et marchait sa droite appuyée derrière la droite du 92e, qui marchait en bataille."
I think that prior to, Seras was behind the Colonne Vuide, but the observation that colonel Penne mentions would have to put them at around 3 O'clock of the Colonne Vuide while Seras is advancing. Because the 92e cannot be deployed behind the 84e which is ployed.
Yes MacDonald did act quickly, but it is still not at the click of a finger. Thought has to go into it, and they already knew their orders prior to, according to Lamarque.
Then both Lamarque and Broussier need to transmit their orders to the bridages. So which bridage was in the 1st and second line...that will give you your answer.
Even D'Erlon is 1815 did not take long to do a passage of lines through the massed battery to form in colonnes...
Nevertheless if you desire to keep Dessaix behind Dutruy with the 92e with two battalions, then you have to break up the 84e so that it is both deployed and ployed.
But there is no way that the 92e was deployed behind the 84e. Nor will I except that the 92e did a compound evolution behind the 84e while manoeuvring in the Colonne Vuide. Both left and right flanks would have been ployed prior to starting the assault.