It's about the workflow

[Sascha Franck]

I use this technique on drumloops ALL the time.
Slice a loop, extract MIDI, replace kick (or whatever).
As said, I do it all the time and it's exactly what makes working with loops interesting.
Sometimes I even record myself tapping onto the desktop, only to replace everything later on.

[NAS Generic]

Imagine having a chop of Funky drummer and replacing the snares with the snares from Amen

It has been the back bone of Hiphop DnB and Jungle and plenty of others for thousands and thousands of years

[NAS Generic]

In fact i used to do it on my Amiga in Octamed about fifteen years ago

[aldi]

hmm, ok, but only replacing a kick or so isn't what i thought of is ment. (this i do also on real drumtracks). i thought he want to replace some parts of the loop with other parts of loops !!! it's no problem to replace just the kicks or just the snares with ONE sample. you can for example delete the kicks from the sliced loop and trigger the kicksample by midi.
and yeah right, ther is stuff like aphex twin stuff where replacing loop slices with loop slices makes sence. (by the way i have programmed BombThatBeat (really the first VSTi beatslicer ever back in 2002 where not many where thinking of slicing beats "many haven't understood the concept of it, now everyone seems to know) so i knew a little about that)