I wired up an old Univox Strat with a 3-way pickup selector for neck-both-bridge, and a mini-toggle to engage/disengage the middle pickup. So, it is effectively a "Tele" with the toggle in the off position, and a Strat with it on. It still has the three knobs but the middle is for master tone and the pot closest to the output jack is for middle volume.
The thing to keep in mind with tone pots is that one is always bleeding highs to ground through the tone pot and cap. Ideally, the value of the pot and cap is such that the highs you bleed are above the range of what you want to keep (and can actually hear), although sometimes people like to soften the tone of particularly bright SC pickups by using values that bleed just a bit of audible top end. In effect, it's the same rationale that underlies use of lower-value pots for SC pickups: 250k pots load down the signal a little more than 500k or 1meg volume pots, removing some of the upper treble content that some players describe as sounding "brittle".
If one has several tone pots tied to the input of the master volume, then unless the tone pots are a higher value and the caps a lower value, one ends up bleeding essentially twice as much treble (for two tone pots), unless the selector switch only applies one tone pot at a time.
You can remediate that situation by using something like a 500k or 1meg tone pot to reduce overall treble loss when all tone controls are set to max bright. But then the challenge becomes one of nailing the ideal pot taper so that you don't have to turn down from 10 to 2 to achieve any sort of audible change in the tone. I think that's why so many players like the setup that Reverend/G&L uses. It provides a lot of tonal flexibility with only two controls, and doesn't require any batteries.
