The oft-quoted 'Palm Test' really has very little relevance, although I'll grant it's confidence-making when it 'works' and that's no bad thing.
The KD Rig is a definate fish-catcher and yet I've known it fail the 'Palm Test' regularly when I've tried it.
The problem with doing any sort of test or trying to apply mechanical principles to rigs is almost invariably that they are performed in air and not under the water. I ask everyone with an interest in 'real tests' of rigs to do the following:
Take the outer plastic tube that 'Funnel Web' PVA comes in (large size). Fill a bowl of water and drop a baited rig into the bowl. Now suck through the tube and watch how the bait and rig behaves! This is much more of a realistic test than any kind of assumptions drawn by 'Palm Tests' or any other 'test' performed in air rather than under the water.
What you'll see is that sucking draws a 'plug' of water up the tube (into the carp's mouth) carrying both rig and bait with it. There is a relationship between the weight (or buoyancy) of the hook and bait; light baits or 'wafters' behave differently.
If a 'strong' suck is made to a 'wafter', (simulating a carp trying to suck in what it thinks is a free, natural weight boily), vortexing and chaotic flow occurs - whereas sucking in the 'natural' boily is a more laminar flow.
Try it and see,
