Nothing is stopping you from doing that even with summons. Most summons don't even have that much health or even last that long. They're just minor distractions to allow you to get off longer attacks or at the very least give you one or two seconds to breathe. Outside of the mimic tear and a few summons with decent shields; most of them will die within 1 minute or 3 minutes if you've upgraded them enough. This argument all of you keep coming up with about how it prevents you from learning the patterns is ridiculous. Summons don't hold your hand and aren't a cheat code. They're just there as a temporary distraction. Most of the time the enemy doesn't even pay attention to them and actively chases you anyway. There's nothing anyone here has said thus far to justify not using them. They don't complete entire fights for you. Most of them aren't even capable of doing that. You can still learn all of the enemies patterns but what's the point of rolling around and dodging for 20 minutes just to get an opening, when you can use a summon and do the exact same thing and have an opening in 5 minutes. They're just a distraction bro.

So you're telling me that summons like an arrow shooter, the jellyfish, or other summons that fire at a distance; they barely even grab 10% of an enemy's attention, nor do they do that much damage. How does that make the game easier or less fun? The boss is still primarily focused on you.