You have good instincts. All the instruction in early fencing or sword & buckler fighting is about getting your weapon or buckler in the way of your opponent's attacks. None of the medieval.fightbooks show turning your back to your opponent as a good thing.

This is dramatic fight arranging, also known as combat choreography. Like dance choreography, they do what looks exciting and interesting, not what's real.

It's always natural to try to avoid hits any way you can, and if dodging does it because all else has failed, you'll do it. But it's bad to get off balance. Silver's Practice goes a lot into the importance of timing in combat in the Renaissance, and it really is at any period. Even Salviolo with his Italian style of pure fence never uses spins or dodges. The general practice is to stay on a line with the opponent and, especially once the lunge is invented, getting off-balance is extremely dangerous. Blocking/parrying is where it's at.