I was casually perusing the daily mirror a couple of days ago and I spied that the odds for one twin to win was 15/8 and the other 18/1.

Maybe I'm being a bit stupid here, but from the reasonable amount of the series I've seen it is basically impossible to tell them apart in any way.

Could some BB anorak please let me know where I'm going wrong, and how their respective odds can be so wildly different!?

Hurry up I'm about to go to bed.