Not necessarily same thing will happen in BAC. But The market excitement on that news was overkill. And so the gap up in Index faded.
Trade your own setup. If you don't have expertise in buying falling knife, why try it. Setup selection is key to long term survival in trading game.
Buffett has his setup based on his valuation model. He can still hold a stock if it goes down 50% after he buys it. If you don't have that kind of patience why trade that kind of stock.