I heard that 8% is an overall cost reduction. That does not mean shedding 8% of staff or indeed 8% of staff costs. Its down to the managers to determine how they make those cuts.
For example it could be renegotiating costs with a supplier, reducing travel costs etc. If managers first reaction is to LR then they are probably not very imaginative. It could also be that one department can make 10% cuts and another department rolling up into the same VP could make 6%. So its not just 8% cuts across the board.
Either way managers have to justify it. HR have nothing to do with it other than do the paperwork
I could be totally wrong of course :)