While one can observe general circuit behaviors, one can't produce or even expect predictable results because of the characteristics of the "ProtoBoard."

Yes, I've learned this "the hard way" attempting to extract meaningful results, building relatively low-frequency circuits such as PLL's, simple op-amp circuits operating at audio rates, but even then, the results were not reproducible, nor were they consistent with what one might expect.

With very careful construction technique, and thorough understanding of the effects introduced by the architecture of these boards, one might, occasionally, produce productive work, but it's not easy. Wires have to be cut to precise minimal lengths, supply leads are always needlessly long, and applying bypass is not always possible without unresonable lead lengths.

I once bought some of the very best "ProtoBoards" but was consistently disappointed with the results, even at low frequency and low power, so I've not used them for anything meaningful in over 25 years. I admit I have used them to demonstrate Schmidt-trigger oscillators, and things of that sort. If one is going to construct a meticulously designed and built circuit, it's much easier, and, most generally, better to make it a permanent fixture on a prototype board with proper ground and power distribution and features that allow a wide range of connector sizes and shapes.

I agree fully, that I'd want to use wires with 1.5-3 mm insulation if I were going to be fooling around with 400 volts.

RE