Gday
Yes a high frequency VLF will find very small gold but unlike the sdc they will not handle the very highly mineralised soils in some areas, but you also have to remember that vlf detectors were the predecessors to the pulse induction machines, they would find shallow gold and small pieces on or near the surface but struggled with depth and running quietly on bad ground, initially the pi detectors killed everything else on the goldfields on big gold, but people stated to complain that they didn't get the small gold that they did with the vlf detectors, that's when they started modding the pi detectors, like the sd2000 adding two higher frequency chips (hot chip mods) to make it more sensitive to small gold.
They have come a long way since then, and I have worked places where even a top of the range pi detector will struggle to cope with the ground using dd coils, no hope with a mono coil at all, up until the advent of the Gpx4500 with the enhance mode since then you could work these spots with mono coils, a vlf could not cope and was far too noisy to be effective at all, from experience I would never favor a vlf detector over a pi detector for hunting gold, although I do use a vlf sovereign gt in the goldfields looking for coins and relics and it only because of its discrimination abilities due to the amount of rubbish around.
cheers
stayyerAU