Can anybody recall a game where both these conditions hold?
1. You used trusty steed for silver
2. You won, but would probably have lost had you not done so.
Bonus points if
3. Bag of gold was available but you specifically chose the steed for the silver.
I can see two situations where it could be useful:
1. Mean cursing games, but if the median card in your deck is worse than silver, how did you get a province and win a tournament?
2. Gardens, but surely buying all the provinces is better.