On February 12, she celebrated her 71st birthday, but she shows no signs of slowing down and, if anything, her tempo is increasing.
Harrington, like all top trainers, possesses that innate ability to make the right decisions when it comes to her horses and she did it again last weekend, sending Our Duke on something of a retrieval mission to the Grade Two Red Mills Chase at Gowran Park.
More about that in a second, but first it is worth noting that most of her major achievements have arrived this century, beginning with the brilliant Moscow Flyer, one of the best two-mile chasers of all time.
Her handling of Moscow Flyer did much to catapult Harrington into the top tier of National Hunt trainers.
Moscow Flyer won the Arkle Trophy at the Cheltenham Festival in 2002 and took the Champion Chase in 2003 and again in 2005.
Harrington, of course, has won the three major pots at Cheltenham.
In 2014 her Jezki landed the Champion Hurdle and then last year the greatest prize off all came along when Sizing John took the Gold Cup.
She is now very much on the Gold Cup trail again, with both Sizing John and Our Duke.
What she has done with Our Duke bears the closest inspection.
The then seven-year-old first signposted he might be the real deal when taking the Irish Grand National by 14 lengths at Fairyhouse last April.
For a horse so short on experience, and with 11-4 on his back, it was a stunning display, although it must be said the form has plenty of holes in it.
That aside, however, the manner in which Our Duke went about his business was deeply impressive, as he put 27 rivals to the sword.
On his reappearance, in the JNwine.com Champion Chase at Down Royal in early November, though, the wheels came off big time, with Our Duke finishing a remote seventh of seven finishers behind Outlander.
He then disappeared off the radar for three months, until Harrington ran him in the Irish Gold Cup at Leopardstown on February 4.
This performance produced a lot more questions than answers, with Our Duke travelling reasonably well when crashing into the second last. He was immediately beaten, obviously, finishing a poor fourth behind Edwulf.
It was all most unsatisfactory and, we assumed, with time running out, he would head straight to the Gold Cup.
But Harrington was having none of it and she made the bold move to send Our Duke to Gowran, just 13 days after having a hard race at Leopardstown.
If this horse ends up winning the Gold Cup then running him last weekend will be looked on as a masterstroke on the part of the trainer.
Make no mistake about it, connections can now travel to Prestbury Park in a much better frame of mind, after Our Duke, superbly handled by Robbie Power, got down and dirty to give the ultra-smart Presenting Percy 7lbs and a length beating over a trip, two and a half miles, that was all too short.
Harrington’s charge did batter into the fourth last, but recovered in fine style and the way he fought in the closing stages augurs well for him up that Cheltenham hill.
He clearly comes with a health warning, on the basis his tendency to make at least one bad mistake in the course of a contest is a worry. Right now, though, he tops my list as the most likely Gold Cup winner.
Noel Fehily will ride Our Duke and not too much should be read into Robbie Power siding with Sizing John.
I gather Fehily was booked prior to the Gowran contest.
Kicking seven bells out of the stewards has always been a popular pastime, but it looks as if those days may be over.
There is so much consistency with stewards’ inquiries now that it has become simply impossible to find fault with the outcomes.
There is a definite change of emphasis in Ireland and when a call is seriously close the stewards consistently find in favour of the victim and that has to be applauded.
Last night week, at Dundalk, the 2-9 shot, Port Lions, beat Max Velocity by a head and lost the race in the stewards’ room.
The second was carried across the track by the winner and thoroughly deserved to be given the benefit of the doubt.
Then at Navan last Sunday, Noel Meade’s Dis Donc won a maiden hurdle, beating Willie Mullins’ Antey by a neck.
Dis Donc did tighten up Antey in the closing stages and an inquiry was inevitable.
But most would agree the result wasn’t affected and no alteration to the placings was the right outcome.
Tell me this, who was the genius, or geniuses, hawking Bapaume on the exchanges at Navan last Sunday?
Willie Mullins’ five-year old was best in at the weights, in the four-runner Boyne Hurdle, and was put in overnight by the bookmakers at 6-5, behind even money shot Diamond Cauchois.
The enigmatic Lieutenant Colonel and the 13-year-old Maggio were impossible to fancy and so you would have to say the layers had this just about right.
There were no negatives regarding Bapaume, apparently, if you read the relevant columnists, and yet Bapaume became available on the exchanges at a price that was quite unthinkable.
At one stage those who wanted you to come out to play offered 3.2, which is in excess of 2-1, after you have paid commission, in the event of the horse winning.
Admittedly that did shorten subsequently, but Bapaume was returned at 6-4 and was bigger than that at the off on the machine.
Bapaume duly ran a shocker to fill a remote third behind Diamond Cauchois and Lieutenant Colonel. A funny old game or what!