Dan,
I usually check all of my equipment except for a four piece rod, a reel, and a nymph box that I carry on for insurance and have never had anything lost or redirected in about 20 years of travel fishing. I carry my cane rods when traveling with those; the two I take most often are two piece configurations and I’ve never been asked to check them. But, you can lash a number of multi-piece rods to a 2,800 ci back pack, crammed with an awful lot of stuff, and it still get past the gate–that’s how my brother usually travels.
I’ve never understood why so many anglers have had problems carrying on rod tubes, that simply roll into the crevices of the overhead bins, when the airlines don’t even blink at all the space hogging guitars filling the cabin compartments.