[8307c4]

Just throwing stuff around, maybe it helps, maybe not.

Weight is a consideration but not when the aerodynamics are that good.
But then it comes down to pleasing looks and cost, so we compromise.

This cover is Lamborghini technology, you can not and will not get a better aerodynamic flow than this. Go look at a Lambo sometime, from just behind the top of the roof it slopes down at a straight angle line just like the cap.

And if you play with an aerodynamic car-modeling simulator you will see why:
It is the best aerodynamic line, nothing beats this, absolutely nothing.

So why does a Lamborghini turn me on, but this cap doesn't do much for me?
I didn't say it did nothing for me, but most of it is purely due to obvious FE.

Is it perhaps that Lamborghini realized a minor loss of drag coefficient in favor of looks might sell better? Evidently cost comes to mind at this point, few Lambo owners care about FE, but a cap that sells for this purpose can't cost a whole lot.
That is, a $400 tonneau cover yielding about 12-14% improvement would take 3-4 years to pay for itself, see where I'm coming from?

I suppose in ways this might yet be the best compromise as is, too.
But the balance that has to be struck here is between looks, cost, and FE.
Then again maybe once fuel hits 6 and 8 a gallon suddenly it sells like hotcakes but if you modified it then it doesn't, you never know.

Now the top or roof of that cap does lift, yes?
Because you see my tailgate is broken, I can open it but not the normal way, and I prefer to leave it shut while it still functions some kind of way.
Oh, and the reason I have a truck is for cargo... That is, sometimes some thing is going back there that just might challenge the confined areas towards the back of the cap, so the top lifts to accommodate for this, then it stays in that position without getting all banged around...

Peace out, all spam aside it is a great idea.