A seemingly needless reminder to read part descriptions for your own sanity.
Been playing RO on and off for awhile now, and [INSERT ARTEMIS INSPIRATION HERE] but I've been finally tinkering with X-Planes and such, and seriously: part descriptions are vital.
That boat tail fairing/decoupler? See how the part description says "DO NOT USE THE FLOATING NODE"? Guess which dumb ass took that more as a suggestion.
Anyway, save yourself the trouble of building a jet for an hour, and then spending 2-3 hours wondering why the hell it keeps popping up with "Insufficient Avionics". The floating node doesn't act as an actual connection, so the cockpit was tragically not actually able to control anything.
If you happen to make the mistake and, like me, have scouted the ends of the earth wondering why the hell your seemingly awesome craft can't so much as wiggle a flap—that's why.