I carry on my 4pc rods all the time and have no problems (9' 2pc rods probably won't make it any more), although I was asked what was in the tubes in Bozeman of all places (new TSA recruit, obviously not from the area); reels, too. As far as flies go, I can offer no logic as to TSA's stated policy (apparently they're supposed to allow them in carry-on) - my neighbor had some in his carry-on and got through no problem, while our friend, in the next line over was treated like he was carrying a couple bricks of C4 instead of some boxes of streamers and nymphs. You can print out TSA policy and show it to those clowns and it won't make any difference; if they decide to screw with you, they'll slow roll you and you could miss your flight. Dulles and BWI are the 2 airports where I've seen this so I've learned to prepare accordingly; I always put my flies in my checked luggage (fly tying stuff, too).
Enjoy the flight - don't buy the food and don't look out the windows and you should be fine.
Regards,
Scott