Soft doubling with a hand like Ace-7 has significant implications in blackjack, as it allows players to double their bet while holding a total of 8 or 18, depending on how the Ace is counted. This strategy provides the flexibility to hit without the risk of busting, since the Ace can be counted as 1 if necessary. By soft doubling, players can maximize potential winnings against a weaker dealer upcard while maintaining a safety net if they draw a low-value card.