[eisanm]

I thought of the fact that even as a HU expert it must be very hard to play more than one table at once.

I do not play HU so I won't say it's not doable, but my intuitive impression is that you'd only be playing 1 table.

Thus I believe that even if you had a much larger win rate playing HU, it would not compensate the many tables you could play as a full ring / 6max high stakes player, and also the much lower variance of ring games which is preferrable.