I can absolve you of your ignorance....
Dominae Spiritus Sancti....Absolvo Idiotes....There done!
I however cannot absolve you of the minor sin of "sloth" nicely put. You have to follow the wiring diagrams. It is your car and this is why mechanics make money, it is work. The Headlight switch and hi low switch carry a goodly amount of current and therefore are prone to burning out. In an ideal world...the switch would feed headlight relays. It doesn't IIRC, unless you add them yourself. (a little wiring....a little splicing...)
here, see for yourself.
http://www.pelicanparts.com/944/electrical/944_84_2_1.jpg
Task to redeem your Porsche: go through the current flow diagrams and "pin out" your headlight switch ad hi /lo to see if it has gone bad. it IS possible the hi / lo stalk switch may be bad. The prob as you described i would check hi lo first.
FWIW, when I have motor probs the headlights go on and the hi low operates fine. This doesn't do me much good with the headlights retracted.
If it turns out to be bad headlight connectors or burnt lanterns.....(did you check?) then the car is just screwing with you. They all do that.
Don't chop your fingers!