Cutting a keyset is essentially the same as copying keys to the keys clipboard then deleting them.
To cut keys
The Current Time Indicator moves to the clicked position and the key is now selected.
The range of keys is now selected and highlighted in red.
If Time Range-All is on in the Cut Keys options, all keys for the current object are cut. If Time Range-Start/End is on in the Cut Key options, only keys between the specified Start and End time are cut. If Time Range-Time Slider is on in the Cut Keys options, only the keys between the Range Slider’s Start and End times are cut.