Paul Davis of Hike-Lite blog
has more aesthetic than weight-shaving reasons for tarping:

On a perfect night a tarp provides the user with an incomparable sense of connection with the outdoors. Waking up to a sunrise under a tarp is an amazing experience.


So if you can afford to own a tarp system for occasional use in ideal conditions then it can work very well. But in my opinion the benefit of the tarp is the connection it gives you with nature rather than a saving of weight.

Waking is fine, but for me the problem is getting to sleep — nature keeps wanting to wake me up. Although, frankly, I think if I hauled a Simmons Beautyrest into the woods I’d still be tossing and turning.