Nearly seventy grand!?! 
On second thought, it might be worth it just to be able to park in the "hybrid-only" spaces at Ikea. What a riot to sit back and watch the outrage on the faces of passersby! 
Actually if you take into consideration all of the optional content included with the 2-mode hybrid Tahoe/Yukons they are not a bad value, at least compared to the fully loaded LTZ/SLT models which are only ~$4000 less.
For instance the 2-Mode package includes the following "extra cost" options:
3rd row seating,6-way power leather bucket front seats (both) with center console, DVD/GPS based navigation system with LCD screen, 9 speaker Bose RDS audio system with XM, subwoofer, Bluetooth voice control and 2nd row controls with headphone jacks, Tri-zone automatic climate controls with 2nd row controls, rear A/C and heater, rear view camera system, ultrasonic rear park assist, intermittent rear wiper/washer system with Rainsense, overhead console with universal programmable home remote, electrically adjustable pedals,leather wrapped steering wheel with radio controls,automatic locking rear differential, 18" wheels and tires, real time active suspension system, HD trailering package with 2" receiver hitch, 7-way plug and electronic brake control harness, rear 110V accessory inverter outlet, electric tire pump and inflator kit, remote vehicle start system, as well as 37HP and 62 more LB/FT of engine...
So much of the additional expense cannot be directly attributed to the 2-mode hybrid drive
Still I understand it's not everyone's cup-o-tea
But if you need a larger vehicle to meet your needs the additional economy might help you make the payments

WopOnTour