It doesn't: blocking isn't instant, you don't get hp instantly, you don't suppress enemies that are outside your radius. You can't just do blocking periodically, you either hold and disable the group of adds, while getting some healing to keep you going while you disable, or you don't block at all.

Learn to properly move while blocking by using jumps.

What does that accomplish? Because that doesn't make enemies miss at close range

Just slam spam on bosses if you are determined to use this weapon to dps. Trash mobs are your weapons.

you need to kill trash or it kills you while you're running towards the boss/miniboss. I'm not saying boss dps is the goal, I'm saying that if you want to do any kind of combat (killing adds is my context in particular), it requires built in sustain somehow, through the virtue just being completely close range in-your-face based.

like, the reality of doing the slam on the boss is he'll rapid fire you in the face while you run at him, then when you slam, he'll stomp and finish you off. if you run at him, block and slam, he won't kill you instantly, you'll get more or less full hp while you block, but he'll stomp you during the slam animation and you'll be close to dying or dying afterwards. it's just the reality of those kinds of weapons, and swords bypass this by either absolutely destroying the elite instantly, using Well of Radiance to get heals or even rift, while absolutely destroying, or getting lifesteal from Lament (while AD).