I've had chains jam when they fail...between the swingarm and sprocket, frame, engine, etc. If it jams up, it will twist and or visibly stretch. A few extra links of chain and a couple extra masterlinks allows you to remove any twisted, kinked, or over-stretched links.
Is it worth hauling? That depends on what the consequences of being stuck are...if your in most developed areas of the lower 48, not worth it; if your in the middle of Mongolia, worth it. In between, you've got to draw that line...
I also agree with dekruyter, if the risk of being stranded is managable then its part of the adventure, but I take a certain satisfaction of knowing I'm totally self-sufficient (even if I'm within walking distance of the next exit). Then again, I patched a tire 3 times in an hour to get home rather than walk home and get a trailer (about the same amount of time, but more satisfying).
06 DL-650 Wee-Twin Baby!!
86 XL-600R Old School Adventure!