no idea about things in the US, but for international travel here are a couple of points:
both singapore airlines and silk air have sports equipment allowances
air france has just implemented an official policy for sports equipement surcharge whereby you pay a minimum fee ( i thin 40 euros for international flight) and you get up to 20kg of surcharge, eliminates the lottery of praying each time you check in. i am assuming that due to the merger with klm, that his policy will be available there as well, but have not seen it written anywhere.
and if you are lucky enough to fly in business class then things get easier.
all flights going through london or australia have limits on the max weight allowed on one baggage, 32 kg, this is due to labour policies in those countries for baggage handlers, this also means that if your flight will transit by anyone of the airports in those countries you are subjected to that limit.
i am currently ending a trip, nice-frankfurt-singapore-manado-manila-yap return and have not had an issue yet with 48kg of checked luggage and about 30kg of hand luggage (though i may not see my luggage for a while as i checked it all the way through from yap to manila to singapore to frankfurt to nice, and i am writing this as i am flying between SIN and FRA
)
hth
/paul