Five Go Mad In Feather Boas would have been the title of the fly-on-the-wall documentary.

That's had anyone actually been making a fly-on-the-wall about the group of women making their way to Manchester via the 9.17am Brighton-to-London train last Friday.

I was having a late start and had intended to catch 9 o'clock train but, on arrival, discovered it no longer existed, at least not until August 6, when engineering works would be finished, so would have to get the 9.17.

In theory, this train gets you into London for 10.10 so it was still a fairly worky sort of train, with a fair number of media types (who don't really have to get to work much before 11) on board.

I sat down in a group of four seats, diagonally opposite a man reading The Guardian and a book about metaphysics and, shortly, we were joined by the aforementioned five, not yet resplendent in feather boas, but noticeable by the fact that they were five women, together and in high spirits, who obviously knew each other well and were off on some sort of girls outing.

"Did you phone Jackie?", "Is she going to meet us there?", "I can't wait!", "I'm so excited!", "Do you think Mick will manage 24 hours on his own without killing the kids?" and similar phrases were being bandied across the carriage, to the slight annoyance of the metaphysics reader, who was caught in the middle of it all.

"By the way, how did you know I had a new laundry basket?" asked one to another, seated farthest away from her.

"I was on a bus and I saw you walking down London Road with it," came the reply, at which point metaphysics Guardian man could take it no longer and asked if one of the women would like to swap seats with them.

They swapped, leaving the five in a tidy cluster, in which they felt more at ease and more able to discuss matters more intimate than laundry baskets; such as when they were planning to get pregnant again and how many attempts it had taken them before they hit the jackpot the first time.

"Well, I'm going to try for another when we get back," said one. "Well, in a few weeks anyway. I don't want anyone thinking it's Robbie's baby."

Robbie, I learned from eavesdropping (the conversation was pretty loud so it wasn't strictly eavesdropping), was Robbie Williams, for whom the five had forsaken their partners and children to see in concert in Manchester.

"Have you learnt the words of Let Me Entertain You?", "No, but I know No Regrets off by heart. I love it when he sings that. He looks so vulnerable!"

"Claire is completely in love with him," said one. "Well, we all are, aren't we?" said another. "No, I mean completely in love with him, like she really hopes he's going to pick her out from a crowd of 3,000 people and ask her to marry him."

"Well, I'm hoping that as well," said her friend.

"Do you think Mick will remember to put suntan lotion on the kids before he takes them out?"

"I put it on Jack myself before I left. He was still asleep but anyway . . . "

"Robbie is going to notice us, you know, because I've got us all a present . . . " And from her bag she produced five feather boas of varying shades: green, red, pink, yellow and purple. Lovely, if a little hot on the hottest day of the year.

"That's absolutely fantastic!" they chorused. "He'll notice us in these . . . "

In a state of excitement, they wound the boas round their necks on the packed train. I wonder if Robbie noticed them . . .