trot out

The Japan Times 9月24日付のNews Headlineからの引用です。
Abe trots out tax hike issue again before snap election to boost LDP chances
"trot" に馬の速足や小走りで走る意味があるので "trots out" だと阿部首相は税の問題から逃げたように思えますが、消費税を10%に上げる話を持ち出したのですよね。辞書で "trot out" を確認します。
・Oxford English Dictionary: Produce the same information, story, or explanation that has been produced many times before.: everyone trots out the old excuse
・Collins Dictionary: If you say that a person trots out old ideas or information, you are criticizing him or her for repeating them in a way that is not new or interesting.: [informal , disapproval] Was it really necessary to trot out the same old stereotypes about Ireland?
・Cambridge English Dictionary: to provide an excuse, idea, opinion, or fact, especially one that has been used often before or one that is silly: You trot out that argument whenever I try to discuss this with you.
何故この様な意味になるのか不思議に思い色々調べると、馬が上手に "trot out" 出来るのを何度も自慢することから次のように他のことでも何度も自慢することの意味になった様です。
・bring out and show for inspection and admiration; "His novel trots out a rich heiress"; "always able to trot out some new excuse"
・to bring forward, as for approbation or admiration, esp repeatedly: he trots out the same excuses every time.
今はその自慢や前からの話を持ち出すことを批判、皮肉をこめて表現する様になったのですね。