most airlines are only let you bing one pice off baggage wich is around 20 Kgs with most airlines and low cost airlines it 15kgs rules say one pice off baggage can be 20kgs
Answer is airlines dont want you to bring bags as check in you olny deal with one person but you bags have lot off people to handly .
let see from check in - it gose airside has to picked up and put on to the van ( if early it put aside ) then there the driver bring out to the plane 2 guy to take off the van 2 lads under plane , now if Customs want to see it that 3 - 4 more people
the days off travel have changed
look out for shipping company that do ship your bags , see this companys in Dublin , madrid and rome (main airports )
2 years ago in madrid i wore 2 jean 3 jumps so wont have to pay airline Excess cost , when ask was i ok and replayed it cold place i going to lol