I'd like to introduce two terms, tempo and pace. The concept of linear movement gives Bushka an unusual flexibility in both. They tend to lose much of their meaning once kings come into play.
Pace is calculated by giving one point to each man on the bottom rank, two points to each man on the second rank, and so on. It does not depend on mobility or the opponent's position (though the difference in pace of course does).
Tempo is more difficult to calculate. Roughly speaking it is the number of moves a player has available. In the opening and middle game, it is usually the number of moves a player has available behind a frontline. Since tempo concerns the number of moves, it may (and usually will) be affected by the opponent's moves.

In the diagram, the player to move loses the game. Of course this position is as artificial as it is double-edged, but the point is that there are many positions where tempo is more crucial than pace. White, if he were to move, would still lose, despite 20 tempi advantage in terms of pace. Making much pace is good in an open game: you go for the back rank. Making little pace is good in a closed game: you need tempo-moves behind the frontline. As far as anticipating the nature of the game goes, the decision whether to keep men back is a strategic one, and quite beyond the scope of this introduction.