OK all you Infinity RS 1A/1B Beta speaker owners..

Not recommended......... The crossover has been
criticized (correctly) as not being up to the standard
of the rest of the speaker system. Nevertheless, it
is necessary to use some type of crossover so as not
to overdrive the mid/tweeter panels with a full-range
signal. Additionally, the crossover has the servocontrol
network for the bass towers.

Rwd,

I think you're referring to bypassing the active subwoofer control instead of the passive crossover in the base of the mid/twt columns.
Yes, this is definitely recommended. You would need a preamp with 2 sets of outputs (or a high quality Y-connector. Simply run one set of cables from the preamp to the amp (preferably tube) driving the mid/twt columns. These columns have a built-in high pass filter that rolls off the bass under 110 Hz.
Another set of cables would go from your preamp to the active sub controller and then to the bass column amplifier. Some people in the past have bypassed the high current protection diodes in the mid/twt columns and the level controls. I was never brave enough to do this.
Good luck!!!

Just a second pair of interconnect from the pre-amp direct into the power-amp of the high-mids tower.

This means that to able to do this you're pre-amp must have a second pair of pre-outs

Alex