Strategy and principles are not the same thing. Principles are the engine that drive and power your techniques. Strategy/tactics is how you approach a confrontation, how you create opportunity to apply your techniques. On some level, yes you always need to pay attention to distance. But, in a competition such as a boxing match, you have time to develop more sophisticated strategies, things like fakes and setups to lure an opponent into a trap. When a fight is scheduled to go a certain number of rounds or minutes, you can employ a lot more sophisticated strategy like that. You are facing an opponent who is also trained, you both know the terms of the confrontation, and you both approach the fight with some level of caution. In a fight, you are looking to end it very quickly. You are not there willingly ( unless you are the instigator, and then you are a predator and an a-hole) you don't know your opponents level of training or experience, and You don't have time to set traps. You need to drop him right now. So you need to be very direct and very aggressive.