But the 61-year-old says there is still no thrill like training and driving a top horse which Stent, winner of last Saturday's A$100,000 Australian Trotting Grand Prix, undoubtedly is.
His belief in his stable star, coupled with the conditions of the Great Southern Star in Melbourne this Saturday night, suggest you can teach an old dog new tricks.
The Great Southern Star comprises two A$50,000 ($53,000) heats run at 7pm and 7.31pm Melbourne time with a A$300,000 final at 10pm.
It is based on the famous Elitlopp in Sweden which has proven so expensive and elusive for Australasian trotters and that also extends to the GSS's conditions, which is where De Filippi realises he will need to be decisive.
Racing twice at group one level in the same night is tough enough but the connections of the finalist get to choose their own barrier draws in the order they qualify in the heats.
With sprint racing around Melton being notoriously biased toward those racing handy, the option to choose barrier one or two for the final is crucial.
Stent has the huge advantage of drawing the ace in his heat and De Filippi says with a heat victory ensuring he can choose where he starts from in the final, he will be getting aggressive come Saturday night.
"He has always been a horse I have looked after but I realise Saturday is a little bit different," says De Filippi.
"I will be asking him to show more gate speed this week in the heat and try and lead and stay there because then we are masters of our own destiny in the final.
"And I think he will be able to show it [gate speed]. He has natural speed, it is just that I haven't asked him much in the past."
De Filippi admits he has never raced a horse twice in one night before, even though he cut his teeth on the rugged South Island circuits where two races in a day were not uncommon.
"It has never been my style but this is a magnificent series and a A$300,000 final.
"And he is coming into it on the way up. He feels good and is really fit so I think he will handle it.
"But I must admit I don't know much about the whole two races in one night thing."
Stent is already profiting from De Filippi's patience as he is in career-best form after being allowed to dodge Australian campaigns the last two seasons.
"His owner Trevor Casey has been good enough to back my opinion and it is now paying dividends," says De Filippi. "And being the type of horse he is he could race on for another four years."
That could see Stent put together a huge bankroll as the money on offer for trotters around Australasia continues to grow and Stent definitely knows how to claim a cheque.
In his past 28 starts dating back two years, he has won 12, been second 12 times and third twice, with this only two unplaced runs being when he galloped away in the Rowe Cup last season and when he became tangled up with the starting tape at Alexandra Park in December.
He meets much-hyped Aussie trotter Blitzthemcalder in his heat this Saturday but the other, later heat looks much stronger, including Flying Isa, Keystone Del and defending champion Vulcan.
The series has been robbed of some Kiwi interest though through injuries to Peak and The Fiery Ginga and Stig going sore after racing at Addington last Friday, while the connections of Master Lavros, Irish Whisper, Habibti and Sovereignty have decided to bypass it for form reasons.
Great Southern Star
Where: Melton, Victoria.
When: Saturday night.
What: Trotting series, with two heats as races 3 and 4, with final as race 9.
Who: Many of the best trotters from around Australasia.
How much: A$400,000 in total stakes.
