I once - long ago - rebuilt a transmitter that I had designed using 'regular' components in the air on a circuit board. It took 6 tries to get it perfect, and every time I learned about a new assumption that wasn't exactly spelled out anywhere but that really made a huge difference in how the circuit operated.
The electrical schematic was identical every time, the only thing that changed was the topology in space. And the difference between iteration #1 and iteration #6 from a performance point of view was huge, much larger than you would have ever thought could be the consequence of the very subtle changes to the various trace geometries.
No matter how much you know - or don't know - about the way electrical fields interact with each other be prepared to be surprised, this stuff is simply hard when your circuitry goes beyond a minimum level of complexity.
Interesting tidbit: many years later when designing the windmill stator/rotor/coil assembly some of this knowledge came in quite handy.