Hi all, yes, this option C will be fine for up to the maximum number of cars i.e. 6.
This is not a problem because inside the ARC PRO the exact same drive circuit powers both lanes anyway (it’s just that the signal polarities have reversed for other reasons). For 4 or more cars you need two standard PSUs to be plugged in (as per Scalextric instructions).
Just to clarify a point of detail, way back when I first proposed option C, what I had in mind was exactly as per Blagard-01’s above diagram. However more recently I have been proposing an alternative way to implement Option C to achieve an identical ’electrical‘ effect - by simply cross wiring the rails of a single lane at the point where the dead spot is formed. I show this as the point marked X in my earier rough ‘tty‘ diagrams. This keeps the modification effort to one lane only. I know an updated diagram is required to add further clarity and I hope to share this tomorrow along with some nice photos the little red mini in action on curved lane changers!
I hope this helps...