Brothers, here we have a slight misunderstanding caused by the difference in terminology. In Eastern Bloc, we do not have such a thing as “partner drills” (or rather, it means completely different things, it's pair exercises without gloves).
"Partner drills" are called "conditional sparring" or "sparring drills" as opposed to "free sparring".
And these exercises are carried out precisely in the form that lead to free sparring, a kind of imitation. All strikes are performed at full speed, at full strength and exactly where you will hit in a real fight, both partners move arbitrarily, apply all types of defense, etc.
For example, one of the basic types, for newbies: we move freely, my partner throws single jabs|crosses, I defend with slips, ducks, blocks, sholder roll. And when I feel that distance is OK, stars are in correct places, Mars in the moon phase
, I catch the punch in my open right glove and answer with 1-1-2 to the head, in response he hits with left or right straight, i slip left or right and continue my attack with straights moving by opposite legs, finally he check is my defense in place with control jab or I fall back with a jab myself. And the more advanced the fighter, the more attack / counterattack options “wrap up” on this basic combination. That is, after a left slip, I can continue not with a straight, but with a left hook to the body OR with the right overhand, my partner can now throw not a single, but double hits, etc. I think you understand the idea.
These exercises are close to sparring, but there is no such strong psychological pressure as in real sparring. So you can try different techniques, new moves. But you get hit, feel pain, etc. And if you can't do the studied combination in such a variant, you will not be able to do it in real fight.
I apologize for the boring wall of text
.