It's an interesting hand. E had opened 1H on his or her (or I guess their) 11 count and stiff spade. Very reasonable and anyway it was stipulated by the problem. This does two things. It allows declarer to place all of the high cards, and it prompts the lead of the stiff heart and subsequent ruff. W is getting one spade trick even without a ruff and is not getting tow sped tricks as long as declarer hops up with the diamond A when Wleads the T at T3.
And yes, as you note, the plan then is to come down to the heart J9 and the diamond Q, and for the lead at T11 to be on the board. If after 7 tricks declare plays two rounds of clubs and then the last trump, then he has no entry to the board so E tosses a heart under the trump, saving the diamond KJ.
On a diamond lead at T1, the hand goes down, losing one spade, one heart and two diamonds. Without the opening 1H call by E, possibly W might choose a D lead. He knows he is getting a spade, or at least he is pretty confident of this when holding JTxx, so he might well decide not to seek a ruff when the T987 in diamonds looks like a nice safe lead.
In playing these Dare hands I try hard not to think "Oh, this is a Dare hand, so of course I have to do something unusual". I would rather that they did not have announced themes. A hand is a hand. But that's just me. I need to think about the hand rather than think about what the hand is illustrating.