8 core could be used with an 8 pole speakon to provide a single cable run from a rack of amps which can then be split to feed different cabs in the stack.

I've seen the 4 core stuff used this way. Active crossover feeding a pair of amps for mid/top and bass. This is then sent down the single run (per stereo channel with 4 core) and into a splitter box which would then run to the separate cabs. The 8 core stuff could run the whole lot in stereo in a single run.

Here's a 4 pole splitter:

http://www.canford.co.uk/commerce/resources/catdetails/2479.pdf