Hugh--Do you (or anyone with long experience on mountain streams) by chance recall any old-timers who fished what were, in my boyhood, called "three-fly casts." This involved tandem-rigged wet flies (most often Yellarhammers or the wet fly form of the Royal Coachman) fished using a quite short cast (15 or 20 feet). Sometimes, but not always, the flies were attached to the main leader by dropper lines of a few inches. I recall seeing the technique used fairly often, and I know it was highly effective. Alas, I did not pay as much attention to the rigging as I should have, since at the time I was almost entirely a dry fly fisherman.
From what I remember, especially in terms of watching old fellows who used this technique, it sounds a lot like the Czech approach.
I did watch a guy use it on the Nantahala River perhaps a decade ago, and he was catching trout like nobody's business.