After opening his account over fences in impressive style at Navan in mid-December, the six-year-old was the 10-11 favourite to follow up in the Irish Stallion Farms EBF Rated Novice Chase.
Robin Des Mana led and was still a big threat early in the home straight, but Goose Man knuckled down admirably to see him off by a length and three-quarters, and the Close Brothers Novices' Handicap Chase at the Festival could be his next port of call.
Taaffe said: "I brought him back to two (miles) because he has learned how to put his feet under him and gallop, which he didn't a year ago - experience of racing has helped.
"He'll have an entry in the Close Brothers Novices' Handicap over two-mile-five. He's going the right way and he's a horse I like.
"It's great to win over two when he's really a three-miler."
Goose Man was one of two winners on the card for Andrew Lynch, with the leading rider later steering Henry de Bromhead's 7-4 favourite Celtic Rising to a ready success in the Sean Graham Bookmakers Maiden Hurdle.
Gordon Elliott rarely leaves Down Royal without a winner and struck gold once more with Gun Digger in the Silks At DownRoyal Rated Novice Hurdle.
Ridden by Jack Kennedy, the 2-1 shot pulled nine lengths clear of Guided By You, with 15-8 favourite West Coast Time only fourth.
"He's a grand, big, honest, galloping horse," said Elliott.
"He's a big chaser for next year. Whatever he does is a bonus until he goes jumping fences.
"Jack said the further he went the better he got in that ground. He'll win plenty of races in that ground."
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