Right im vetoing "jumper" as the terminology for this as it makes no sense lol. Your not jumping anywhere, your staying in the same league! I can only think that the OP got lost in translation and meant "thrower" i.e throwing the season to stay in the same division.
I prefer the original terminology of "tanking". Think some ones trying to leave a T11 legacy, which already belongs to someone else (july forth I think)
Being able to spot a tanker is immaterial IMO as they'll probably just look like a scout buyer? maybe younger players. Also next season when I reap the benefits of tanking ill have no guilt as someone else this season has benefited from me tanking as I reckon id have finished in the top 3 at least