Timothy
Using fuel crossfeed to laterally balance any aeroplane will have no effect on directional or longitudinal trim that cannot be properly (and normally) dealt with in the usual way. So it has no aerodynamic disadvantages or complications..
Whether you are increasing your chance of a fuel management pigs is another matter and depends on you as well as how big the imbalance needs to be to trim wings level. I would have thought it need be only small if you have set your fixed aileron tab to give approximately wings level in the cruise config.
BTW I have never noticed any august people here, just those who have tended to specialise in aspects of aviation that (by and large) avoid boring hours in the cruise.
Regards
John