At the weekend I was trying out the invisible tri bars on my Specialized Roubaix.
The lack of substance made changing gear a bit difficult. I may need to add more padding ( some pipe lagging maybe ) but overall these bars are great.
I think the non-existent bars are worth as much as 2kph under optimium conditions.
And of course they weigh nothing
To use the invisible tri bars on your bike, first watch the Tour de Suisse to see how Cancellera does it. Next, make sure there are no camera mounting clamps and other bits of odd equipment clamped to the bars where you’ll be putting your elbows. Then find a bit of quiet straight road and go for it.