I worked as an assistant for 12 years, flying all over the world with gear. In all of that time and all of my time flying with my own gear, the only head to break was a ringflash tube that wasn't packed properly by someone helping me out. I don't dismantle anything tube-wise, but do agree that things should be packed VERY tightly to avoid shift and rattle. I am annoyingly anal with how I pack gear (some guys I've worked with get pissed when I unpack a case they just threw together and repack it to my liking, so be it).
One trick with the profoto heads is to put the reflector on the head before you cap it and then wrap the head cord around the cap, between the cap and reflector. You can also do this by wrapping the head with the cord and then putting the reflector backwards over the cap (as long as the cord fills the reflector in some way).
Also I've always ONLY used Lightware, TenbaAir, and Tamrac Rolling Studio cases. When I check your cases, I try go to the TSA counter with them. If I'm polite they have always let me repack the case after they rummage through it. That way it is packed the way I want. I then lock it with a TSA lock after they have done their thing. I've done this with domestic and international.
Best of luck!