The phrase "ago realized" is not correct and does not make sense in written English.
It seems to be a combination of two separate ideas that do not work together grammatically.
Example: "I realized my mistake a long time ago."
Alternatives: "previously understood" or "recognized earlier".
"But I long ago realized they're in a different league than I am.
Political leaders long ago realized that the easiest shorthand for being "tough on crime" was to support capital punishment.
Traditional classroom educators long ago realized that when you crowd ten or twenty or a hundred students close together, learning, by default, becomes a social experience.
Nascar long ago realized their survival depended upon portraying themselves as an inclusive organization, acceptable to all races in all regions.
"Obviously it would be an honor to be given that kind of recognition, but I long ago realized they do what they do.
Elected officials, she said, long ago realized that aligning themselves with breast cancer advocates was a good way to win women's votes.
Then I saw that picture again a few years ago, realizing what I do now, that we're creating these characters for the purpose of a fashion picture.
A few years ago, realizing that most of his clients were too sick or too far away to visit him at work, he stopped wearing office attire, leaving on the wicking fabrics he wears on the ferry.
Four years ago, realizing that many of the books were disintegrating, Mr. Lansky set out to digitize the collection to preserve it and make some of the hardest-to-find titles available beyond a few rare book repositories.
He broke into the business decades ago, realizing solar's potential.
"Many years ago, realizing our advanced age, we figured out the best time to do it was when the church bells would start to ring.
