I will bet part of the stake underlaid in the live market if and only if it means that the overall odds on the full stake are still an overlay. e.g my odds 3.0, get half stake on at 3.4 rest at 2.9, so full stake on at value 3.15.
It’s a good tactic. Similarly, I quite like the idea of splitting a bet between a BOG price in the morning and a follow-up late on Betfair if the market is speaking for, or not going in again if the market is against. You’re taking advantage via a higher stake when field money says you should and via higher odds when it doesn’t.
The inbuilt contradiction in this is that your bets are being influenced by the ‘perfection’ of the late market – using it as advice in effect – yet unless you can beat that market overall the game is futile.
For practical reasons it’s a non-starter for me (I study in the mornings). And the ‘getting on at BOG’ thing still exists for everyone.
Mike