But Palmeiro's ability to look and sound believable no longer matters.
He juiced. And got caught.
That can't be spun, interpreted, denied, avoided or ignored. That's just fact.
To paraphrase Palmeiro's own words: He used steroids - period.
And boy, is he going to be sorry.
If he thinks he can hit his way past the ignominy this will bring him, he's in for a surprise.
This now becomes the second sentence of his career story.
The first sentence is that he spent nearly 20 years compiling offensive numbers that should make him a first-ballot Hall of Fame inductee.
The second sentence is that he was caught using steroids, inevitably casting doubts about how much of his success was legitimate and how much was chemically enhanced.
The Hall of Fame? This could easily knock him out. It's that damaging. Now voters will remember him for being the game's most accomplished certifiable juicer (at least so far) as well as for having that sweet left-handed swing.
Harsh stuff? Sorry, facts are facts. He failed a test.
The best-case scenario for him is that the episode will eventually be viewed like Sammy Sosa's 2003 corked-bat brouhaha - a damaging eye-opener deemed not important enough to undermine his historic accomplishments.
But Palmeiro isn't about to get off that easy.
With the sweeping nature of baseball's steroid crisis becoming clearer every day, a flunked test is becoming one of the darkest, most immutable stains on a player's record, one that raises questions about his very essence and credibility.
Was he a one-time or chronic user? Now you have to wonder.
If he was careless enough to get caught now, in this atmosphere of increased testing and scrutiny, what does that say about his likely habits when there was no testing? Now you have to wonder.
And what about the legitimacy of his numbers? How can you not wonder?
You just get one strike in this game of trust, not three, before your integrity is challenged.
From his comments to reporters yesterday, it's clear Palmeiro is going to insist it was all a mistake; he said he doesn't even know how the steroids got into his system.
"You have to be careful with what you're taking," he said. "You have to make sure that you, you know, see a doctor, you know, you make sure you get your, whatever it is you're taking, your supplement, that you're taking it from a reputable source."
He even said he hoped kids would learn from this and pay closer attention to what they put in their bodies.
"It happened to me and it could happen to anyone," he said.
Here are three problems with that version of events:
Most kids and clear-eyed fans are only going to remember that Palmeiro told Congress he wasn't a user and then flunked a test - period.
Baseball's list of banned substances (one of which got Palmeiro caught) is composed mostly of sophisticated performance-enhancing chemicals, not vague substances that get thrown into supplements you can buy at the mall.
And finally, in today's sports world, soaked equally in chemicals and money, the vast majority of athletes - especially veterans such as Palmeiro - tend to know everything about what they're putting in their bodies.
There is just too much at stake not to know - contracts, reputations, endorsements, health.
"We tell our players that anything they put into their bodies, we should know about," Orioles executive vice president Jim Beattie said yesterday.
Palmeiro wants you to believe he flouted that order and blew it, simple as that. Some people will believe him. Who doesn't want to? Palmeiro has been a terrific player and a class act, and his defense offered yesterday was plausible in many respects. Why would he have used steroids when he was near the end of his career, closing in on 3,000 hits and had pledged his innocence under oath before Congress?
"There was nothing for me to gain and everything to lose," he said. "I would not put my career on the line. I would not put my reputation on the line."
But facts are facts. He had steroids in his system. And the paradigm changes, unavoidably, when a test comes back positive.
Try as a player might, there's really no spinning it, no justifying it, no explaining it. The story is written in ink, permanent, irreversible:
You're caught juicing. And you can never go back.