Thank you (genuinely) for writing all of this down, but nothing you have written is specific to PMod. I get that complex physical effects cause simple models o

Thank you (genuinely) for writing all of this down, but nothing you have written is specific to PMod. I get that complex physical effects cause simple models of the world to break down -- that much is obvious. And of course it's up to you what explanations you are willing to write up for free. But I don't see how any of this supports your claim that PMod is insufficient to high-frequency work when it does not reference any design decisions made by the PMod spec that adversely affect its high-frequency performance. One of the following must be true: 1. The PMod interconnect is specified in a way that inherently limits high frequency applications, whereas it could have been specified in a different way that would allow for them. 2. Something about the design space PMod is trying to solve (off-board peripheral modules connected to a main board through a standard connector) is inherently hostile to high-frequency applications, and no specification is capable of getting around this limitation. 3. PMod is actually capable of high-frequency applications, although most PMod ports are not particularly designed for this. Your original message seemed to be claiming (1), but none of your subsequent arguments have offered any support for (1) that I can see. You have absolutely convinced me that complex physical effects must be taken into account, but that information does not help resolve which of 1-3 is true. To convince me of (1) I would need to see a specific design decision in the PMod spec that makes high-frequency applications impossible, as well as the alternative design choice that would have allowed for them. For example: "PMod does not allow shielded wires, but high-frequency requires shielding" would be a convincing argument if true.