Stu,

I wouldn't waste you time trying to perfect a dual valve system....just modify the throttle body, fit an ALS valve modify the ecu/software and try it....although they are competition cars mine certainly idles very smoothly without the als on...it even idles nicely with the als on lol.....

If you insist on using a dual valve system, do you plan on running both valves during als operation, DPDT switch made? and then only the normal iscv during normal running DPDT switch open?

The switch interupting the power supply to each valve?

If that is your plan i'd say it would work....