jsloan, it's people like you that make the flyertalk community so invaluable. Thank you, for your detailed explanation. Interestingly, I called UA 1K line and was told I would have to pay for everything: UA baggage policy doesn't apply to when another carrier operates the initial check-in (or so I was told). I then called Lufthansa to ask how much I should expect to pay and, interestingly, they cited their "most significant carrier" policy: as I booked through United, and they are operating the trans-Atlantic leg, the LH representative insisted that UA's baggage policy holds (i.e., 3 bags @ 32 kg for me). So in the case of my conversation with the UA representative, either: 1) they punted and played overly conservative, and/or 2) didn't know what they were talking about. Regardless, as per your assessment above and the LH rep's, it seems as though I'll simply be paying for the extra "sport bag" (bicycle box). Thanks, again, for your feedback.