Therefore, if a right-handed fighter stays in a left-lead when fighting a left-handed opponent who uses a right-lead, the fighter will be at a disadvantage since he or she will be fighting an opponent with a different lead. However, if the right-handed fighter switches to a right-lead, while he or she may feel awkward in this lead, the fighter will be on more equal ground with the opponent, since the opponent will now also be fighting an opponent with a lead he or she is not used to fighting.
The "single-lead" and "strong-side lead" theories are not new. Joe Lewis prefers fighting from a single lead. Bill Wallace, who always fought from a left-lead, agrees. He says that it does not make sense to use valuable training time to become mediocre fighter on two sides when you could use the same amount of training to become an outstanding fighter on one side.
Al Dacascos, as well as the late Bruce Lee, believed fighters should train with the strong-side forward. Nature seems to agree since most animals keep their strong weapons in front (tiger claws, snake fangs, etc.). Having the strongest weapons in front allows them to be quickly brought into action. Lead-hand or foot strikes are much quicker than those from the trailing side, and, when the strong side is in front, the strikes have more power. This does not mean that trailing side strikes are weaker. As stated above, you should train the non-dominate side on different techniques than you use on the strong side. Then the trailing side becomes just as effective as the strong side. Then, even if the strong-side becomes disabled, the once weak side may take over.
Most double-lead fighters have a favorite side. If it becomes disabled, the fighter must use the other side. Will that side be any stronger than the weak side of the single-lead fighter? Maybe, but even if it is, it will probably be no more effective than the weak side of a single-lead fighter.