Without IMO. Black Tie is spoilt by a waistcoat. But then, I'm not wearing it so it's your call. Plus it may be hot. My recollection of Balls in my University years (especially Froebel all nighter) was how unbelievably warm it was in a Black Tie.
I agree, no waist coat. I think the stark white of the shirt contrasting with the black of the suit looks good and the waist coat diminishes this. I also think a cummerbund works as it tidies up the waist area. I have a couple of colours and quite like my bright red one.
You do wear a waistcoat with white tie evening dress (tails) but that is a white waistcoat with no back to it. Don't get the opportunity to wear it that often but when I used to play in an orchestra it was the norm and looked great.
Black waistcoat with Scottish evening dress as magnatom points out, kilt or tartan trews.
Cumerbund optional on a single breasted dinner jacket.
It is all down to taste at the end of the day, people used to wear all sorts of things in the seventies particularly in the US.
We used to have to wear "Mess undress" and a cummerbund was essential.
However we used to cheat with the shirts!
I used to have an immaculate white dress shirt, which looked fine when jackets were on but as soon as the jackets were off it was a different matter, I had a tropical scene with parrots on the rear of the shirt, one sleeve was bright green and the other red.....