Answer
You (3rd seat, both vulnerable) are on lead against four hearts:
What’s your lead? Our experience is that leading an “unsupported Ace” (that is, leading the Ace when you don’t also hold the King) against a suit contract tends to lose matchpoints in the long run. Although it’s true that this lead can gain (for example, when partner has a singleton and gets a ruff, or when partner has the King and it’s important to cash those tricks right away), we find that — more often — this lead gives declarer an undeserved trick (for example, declarer has Kxx in hand and xxx in dummy, or Qxx in hand and Kxx in dummy). We recommend leading the Jack of spades.
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