Checking to the river makes the most sense when the promotion is large (imagine a $1,000,000 bonus for aces cracked) and zero sense when the promotion is small (imagine a $0.01 bonus for aces cracked). Why? You realize that if you WIN the hand, then you've lost on an opportunity to take a bigger pot with a strong hand. Once the pot is $20, I would check my aces to the river.
