key words from page 21, page-6

It's all about cost, time and the environment ... the latter being particularly important to our FP partners.

Operating 4 wells from a single pad in itself drops drilling cost by about 10% according to Continental resources. Putting a lift and roll rig on the pad [ I guess a bit like a land based jack-up-rig ] means that significant time and money is not wasted rigging down then up again for consecutive wells on the pad. I don't have savings number on the skiddable rig.

cheers