Just my experiernce here...

I set up a Ti frame with a Brooks Ti B17 with the drop handlebars at or just above the saddle height. I toured Vancouver Island with the bike as its initial major outing, and did a bit of randonneuring training with it as well as some additional short tours. But that Vancouver Island trip resulted in a sore sitbone that just wouldn't go away for something like three years. I think it might have been a case of bursitis.

Anyway, in our new phase of randonneuring, we have been tinkering with our bike fit, and Machka wanted the bars on her Bike Friday Pocket Llama lowered to relieve some pressure one one of her sitbones. It seemed to help, and we did the same with her Marinoni.

I got to thinking about doing the same with the Ti bike, did so, and lo and behold! The sore sitbone has now recovered and I've ridden a 200 and 300km randonnee since.

So I would suggest a bit of caution with the set-up. At first sign of sitbone soreness, think about lowering the handlebars incrementally. It will tilt your pelvis foward and change the angle of pressure on the sitbones.

I've since gone through my Thorn touring bike, as well as my Bike Friday and CF Merlin dropping the bars by 10mm or so. Having a ready supply of 5 and 10mm spacers helped with the integrated headsets and such.