Complex sentence: Good field craft is especially important for the survival and effectiveness of infantry soldiers and special forces and in the more effective units a huge amount of attention to detail as well as much time and effort is devoted to making good field craft second nature.
Split into simpler sentences: Good field craft is especially important for the survival and effectiveness of infantry soldiers and special forces. In the more effective units a huge amount of attention to detail as well as much time and effort is devoted to making good field craft second nature.