I.E actors and actresses that were passed over many times and were finally awarded an Oscar but when you read between the lines you feel they were awarded for a body of work and not that single performance.

Off the top of my head:

Paul Newman for The Color of Money
Sean Connery for The Untouchables.
Al Pacino for Scent of a Woman.

Disagree about Connery. He steals the movie with his performance. From the day the movie was released people were taking about him being a shoo-in for the Oscar.

Scorsese. Although the other nominees that year weren't for great films.

Alan Arkin

John Wayne for True Grit

Don Ameche for COCOON.
George Burns for THE SUNSHINE BOYS.

Such awards are designed to honor old-timers who are never gonna get an Honorary Oscar or an AFI Lifetime Achievement Award. These awards are the next best thing to reward them for their astounding career comebacks decades after their initial Hollywood stardom peaked.

Henry Fonda - On Golden Pond
Jack Palance - City Slickers
Tatum O'Neal - Paper Moon

Humphrey Bogart - The African Queen
Art Carney - Harry and Tonto

Tatum O'Neal - Paper Moon

Brilliant!

Well, he deserved that one.
I doubt that was really for a body of work. He was a TV star, not a movie star. Still that one stings since he beat out Pacino in Godfather Part II and Nicholson in Chinatown.

I might add Judy Dench - Shakespeare In Love. She was great, of course, but she was in the film for what, eight minutes?

Rod Steiger - In The Heat of the Night (he beat out Newman in Cool Hand Luke, Hoffman in The Graduate and Beatty in Bonnie & Clyde)

Disagree about Bogart. It was still early in his starring career. He was only about 50 and doing lead roles for only 10 years. Before that he just played the same two bit gangster over and over in supporting roles. His win was on the merit of that single performance. Nobody had a clue then he'd be dead at 56.

Jack Palance- Anybody believe he had a career that would garner a cumulative Oscar? He won on the merits of that single performance, and a great one it was.

Newman only got his because Color of Money was a sequel and he reprised a role that was Oscar worthy in the original. He was given the award for The Hustler, not his body of work. Had Color of Money not been a sequel he would have lost again. He wasn't out to pasture yet and the Academy would have waited another 10 years and given him an honorary. I believe the thinking was, "He's doing Fast Eddie again, let's give it to him now." He would have won if he'd made Hud 2, The Verdict 2, etc. no matter how good the films were. But they had to be a sequel to one of his previous nominated roles.

Over Marlon Brando in A Streetcar Named Desire, I disagree. I may be wrong about body of work but Bogart's African Queen Oscar sure as hell was a make-up .
He should have won for Casablanca or he should have been nominated in 1948 for The Treasure of the Sierra Madre and won.

Russell Crowe when he won for Gladiator; the Academy was making up for his loss the previous year when he was nominated for The Insider. So not really for "body of work" per se.

Al Pacino for Scent of a Woman. Sure, it's a great performance and he makes the movie as good as it was, but he had been nominated for much better performances over the past couple of decades before his win.

Morgan Freeman - Million Dollar Baby

Similarly Robin Williams winning for Good Will Hunting instead of Dead Poet's Society.

Alan Arkin - Little Miss Sunshine

I was in college then and won $500 betting that Newman would win the Best Actor award months before the Color of Money was even released. I actually got paid too, the guy I bet was in disbelief.

The Hustler in my view is one of the greatest movies ever. Very underrated, despite being pretty well regarded.

Similarly, I feel like Denzel Washington's win for Training Day was more for his work in The Hurricane. The Academy was playing catch-up for a few years.

Jessica Tandy for Driving Miss Daisy.

And Malcolm X.

Hey, I take exception to that. It was a great performance.

Martin Landau for Ed Wood is the fist that pops into mind.

Matthew McConaughey to make up for Fools Gold and Ghosts of Girlfriends Past

Anna Paquin - The Piano.

The question was "for their body of work", not simply "body".

Anyway, how can you accurately see inside of the minds of Academy voters from 10, sometimes 20 or 30 years ago?

I have no trouble believing they thought certain lacklustre performances were "the best of the year". Shit, look at some of the movies they gave the top award to.