Decker and Müller focus on the Höhere Taktik for artillery. So for them one important criterion that more than one battery is involved.
I try to answer some of the questions by interpolation, we have the SYW as nice starting point, the revolutionary and napoleonic wars with a lot of new tactics, then a long peace period (still napoleonic tactics) which allowed theoretical evaluation of these wars and finally major changes after 1866. Höhere Taktik - in contrast to Elementartaktik - usually requires not only acceptance/understanding in one armof the army but in all three. When I do not find Höhere Taktik for artillery in Prussian sources published in the 1830s and 1840s by authors who often were infantry officers in the wars of liberation, then I draw the conclusion, that there was very likely no widespread understanding for these problems in theses wars in the Prussian army. Here Müller delivers nice datails and make good arguments why there were these problems.