I sincerely doubt that correct application of appropriate higher-tech gear to any given problem will fail to solve it. For example, a mobile desert force equipped with fuel cells and evaporation stills will - everything else being equal - experience FAR fewer problems than one tied down to a network of fuel and water dumps.

That is not to say that lower-tech-level solutions can't work. *A* particular balance of lower TL and other factors (level of skill, situational intelligence, individual initiative, etc) might well prevail against *A* particular opposing balance of higher TL and such other factors. But in a case where all "other factors" are equal (or even roughly close) between opposing sides, the side with the more capable technology WILL win.

 

Well, mercenaries *used* to be blades for hire . . .

But they were always *supposed* to be troops for hire.

Upon becoming something else (such as the defacto rulers, as in the case of the Praetorian Guard "electing" Roman emperors), then they ceased to be *mercenaries.*

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