like those used by Tilly were in fact faster and more flexible, and the Swedish King made use of them when required, like in the battle of Alte Veste (see picture 3). Armies did start to use thinner formations, but in a slow evolution, and subjected to tactical considerations. Firearms were not so effective as to determine solely the deployment of troops, other considerations were also observed, like units' experience, assigned mission, terrain, or the need to meet a required frontage with an understrength unit. The debate of line vs column was carried through the 18th Century up to Napoleonic times, with a temporary reverse to deep columns in the later campaigns of the Napoleonic Wars. Ironically, depth reduction in cavalry formations was a more permanent change introduced by Gustavus Adolphus. In conjunction with less reliance on pistol fire it had the net effect of favouring shock action over firepower, contrary to the tendency defended by Roberts. Trace Italienne Roberts' linear tactics concept had an early critic in the younger historian Geoffrey Parker, who asked why the supposedly outdated Spanish tercios defeated the Swedish linear formations at the battle of Nördlingen in 1634. Parker instead suggested that the key development was the appearance of the trace italienne fortifications in early modern Europe. In this view, the difficulty of taking such fortifications resulted in a profound change in military strategy. "Wars became a series of protracted sieges", Parker suggests, and open-pitch battles became "irrelevant" in regions where the trace italienne existed. Ultimately, Parker argues, "military geography", in other words the existence or absence of the trace italienne in a given area, shaped military strategy in the early modern period, and lead to the creation of larger armies necessary to besiege the new fortresses and to garrison them. In this way, Parker placed the birth of the Military Revolution in the early 16th century. He also gives it a new significance, not only was a factor in the growth of the State, it was also the main factor, together with the "Naval Revolution" to the rise of the West over other Civilizations. This model has been criticised on several grounds. Jeremy Black pointed that it was the development of the State that allowed the growth in size of the armies, not the other way around, and found Parker guilty of "Technological Determinism". More tellingly, the figures presented by Parker to sustain his