Rory Miller talks about how people have this tendency to stand in front of each other when fighting even though it's possibly the least sensible place to be. Of course, if your adversary knows you are coming, it's hard not to be caught in front, unless you are at a certain range and have the opportunity either through distraction or their movement towards you, to get around them ...
Another reason he postulates for this is the Monkey Dance paradigm - in a dominance type interaction (and dueling certainly falls into this category), it's part of the plan that a 'you' wins in relation to 'them'. Being in front makes sure they know who beat them.
So what happens if 'they' have your number, as it were?
You can't win as 'you' - they know 'you' are coming, can read who 'you' are, and on some level this means that everything 'you' do is a tell .......
Seems obvious, but you have to become someone who can instigate a rash decision, a mistake or cause a distraction in THEM. You need to change, and become whoever you need to become to make that happen. Sometimes it can be 'you', other times it can't.
Sonny was one of the few people I have seen fight/spar/play who could do so as many different 'people', changing his game to suit the moment and the opponent. I always admired this ability greatly, not only because it was fascinating to watch, but also because tactically, it made a great deal of sense.
“If your opponent is temperamental, seek to irritate him. Pretend to be weak, that he may grow arrogant.
"If he is taking his ease, give him no rest.
"If his forces are united, separate them.
"Attack him where he is unprepared, appear where you are not expected.”
― Sun Tzu