Dual volume controls on superphon pre-amp

Buying a superphon pre from my dad and he informed me that it has dual volume controls. Of course I can see that one could control each speaker with corresponding volume controls but what is the purpose of this. Dad does not know and he knows of only one other pre with this system.
It replaces the need for a balance control.
If the two controls are for the two channels it is a damn nuisance. When stereo was first introduced I, and some others, used two mono preamps, because there weren't any stereo ones. I stacked two Heathkit preamps, installed a stereo volume control in one of them and ran the signal from the other preamp up and back.

Some preamps (but I haven't seen any lately) had, for each channel, volume controls at the input and at the output. This lets you optimize the signal level going through the circuitry. My electronic crossover, Ashly, has this feature today, and I use it to allow a high signal level through the digital circuits of my Behringer DEQ2496 equalizers without overloading the crossover or power amps.
Brilliant. Never would have thought about that. If that was the case the designer would have not put an extra control on what is a pre designed to be basic.

Any other ideas?
I have dual volume controls on my Morrison Audio ELAD. It seems like a pain, but I became acclimated to it pretty quickly. Try it for a while.
If it is the dual mono model it does replace the balance...but when stan warren designed it the were mirror image channels so neither channel relied on the other.I really enjoyed mine back then.replaced with higher end vol atteuators bumped it up another level.paired with a bk st-140.Those were simpler days.still think alot of that little preamp...
Roxy54 I am gettin quite used to it and I find that it is actually ok. Of course it helps that replacing my other pre with the superphon is quite an improvement. With that in mind it is easy to deal with and this little pre is amazing. Not much to look at but who cares, sound is what matters. I am not out to "show" a beautiful stack what I look for is amazing sound. What a little gem this old pre is and it's going to get better with a few mods. I often hear "out with the old and in with the new" while that can be correct sometimes I find that embrace the old and don't waste so much money with the new works as well. Some of the best built stuff was awhile ago. Not to say that there are not good pieces being made. What I'm trying to say is you can have great quality stuff, built well, that taken care of will last all of you listening years. It may be "ugly" to some but you are missing out if you base your opinions on looks, age, and trends.