At the finish line on Sunday, conducting interviews while his five-year-old son Macs clutched his leg, he allowed his feelings to flow a little more freely.
“I wish I had tinted glasses, not the rain ones where you can still see my eyes,” Thomas joked.
“That’s what gets me every time, you know, seeing him [Macs] and Sa [wife Sara]. He’s just well into it now and I never thought I’d still be going when he was at the age to really remember it.
“So that’s really nice as well, that he can take it all in and then enjoy it and remember it.”
Thomas’ family have followed him all over the world, been there for some crushing lows as well as the soaring highs.
Having picked him up after crashing out of Grand Tours and nursed him through enough injuries to make a surgeon wince, wife Sara and the rest know better than anyone that these are the moments to savour.
From the start of the stage, through its windiest, wettest and coldest peaks on the Gwent hillsides, right through to its finish in Cardiff city centre, the sheer number of supporters out on the course was something to behold.
Thomas was blown away, almost rendered speechless. In his defence, though, how do you adequately summarise – in the immediate aftermath of a day’s racing – that show of appreciation for a career which has spanned three decades and yielded two Olympic gold medals, three world titles, a Commonwealth gold, countless other race wins and cycling’s greatest prize of all, the Tour de France?
You can’t, not really, but the masses who lined streets and mountaintops from Suffolk to south Wales over the past week did a decent job of demonstrating what Thomas means to people.
And as passionate as they were – the cut-out Thomas facemasks were a highlight – they represented only a tiny cross-section of his following.
Thomas has been handed Welsh cakes by well-wishers at the Giro d’Italia, inspired road graffiti in the French countryside and counts the actor Ben Stiller among his celebrity fans.