Complex sentence: The arrangement of pikemen and arquebusiers used was regarded as too costly, and was not tried again; in subsequent battles, arquebuses were used primarily for skirmishing and from the flanks of larger formations of pikemen.
Split into simpler sentences: The arrangement of pikemen and arquebusiers used was regarded as too costly, and was not tried again. In subsequent battles, arquebuses were used primarily for skirmishing and from the flanks of larger formations of pikemen.