I would like to do that in time because a 90mm stem and narrow bars is way too sketchy on the downhills but as i was a little strapped for cash and got the bar and stem cheap from crc as well as a few other bits (outer cable, cassette and chain,) I DO have a 780 bar and 50mm stem set aside for my voltage so i could try it out putting the grips inwards a little but i felt the ones i got were more suited for it for climbing stuff.
I'll have to play about with it and see what's better but pretty sure you're right about me liking that set up
Where i ride to is mainly uphill all the way and obviously on the way back is downhill I've always been a fan of 50mm stems though with them giving more direct control and wider bars will only emphasize that so pretty sure i'll go to that in the future