I suppose it depends on what you mean by heavy partial reps.
I've found that training the initial deadlift pull (think, from the floor to about knee height) helped my deadlift. This is because being just shy of 2m tall, I've always found the initial pull from the floor a lot tougher than the lock out. If I can get the bar past my knees, then I've got the rep.
You could count that as a partial rep (and I always trained them heavy, though not heavier than my deadlift 1RM).
I've also found that squat holds at greater than 1RM (where you load the bar up with more than you can squat, unrack it but don't squat, maybe just kind of wiggle a bit) have helped me squat more weight.
I've read from Dan John that this can have a strengthening effect around the core musculature because you're having to support the extra weight. I'm not sure if that's the case, but what it did do for me was help with the mental block I used to get when the weight on my shoulders went above a certain point.
Again, I'm not sure if that counts as a heavy partial, I used to move slightly with the weight on my shoulders, just to get used to the feeling, but didn't do anything approaching a full squat.
Lastly, look at the Olympic lifts. If you look at a full clean and jerk, then I'm pretty sure every successful weightlifter has trained the clean portion of the move with weights heavier than they can jerk overhead. The clean is often seen as a lift by itself, but you could argue the same for a lot of "partial" movements if looked at on their own merits.