I am guessing the sub, is a default bet for quadrellas and such...???? Whatever it is, it seems to pop up for a win all the time. Any stats on subs anybody? Or even just clarification about what it is?

If there is a late scratching (which is any time after betting has opened on an event, such as the Quaddie or Daily/Extra/Race-to-Race doubles, there is a sub determined, which is the favourite on the tote just prior to the jump (used to be the fav 15 mins before the jump but this got altered due to manipulation), so a lot of them are going to win.

........