Then you haven't taken into account noise building up in every half inch of a cable that leads from the clamp to the instr-amp. Or do you advocate clamps with built-in ADCs? No objection then, as long as the wires carry digital signal but for the fact that this would cost so much it isn't funny. One might as well stick to off-the-shelf PLC-style rail-mounted IO modules and shunts/transformers then.