At that time, I could barely tolerate spending any meaningful time with my own kids, so I couldn't get my head around why on earth anyone would expect me to feign interest in the trials and tribulations of other parents' little Ronnies and Reggies.
Life with kids is hard work and boring, punctuated by moments of surreal joy that makes you forget all the boring, painful stuff. A bit like childbirth, really. I'm told.
But that forgetfulness only applies to my own offspring. With other people's progeny, I really couldn't be less interested.
"You need to get involved with the school more, get yourself out of the house," my Successful Other Half said in response to my latest tirade about the tedium of domestic chores.
And so it came to pass that I volunteered to join my youngest son's class of 30 four and five-year-olds on a day trip to a children's activity centre.
"You must be insane," my friends said. "What are you even thinking?"
"I've got to do it," I insisted. "Got to earn my keep. My missus did all this stuff when she was at home. I need to pull my weight."
I arrived at my son's Reception class feeling as if it was my own first day at school. Three mothers were already in attendance, marshalling the children into pockets of five. I expected them to eye me suspiciously: What was this man doing here? Shouldn't he be at work? Where's his wife? What's wrong with him?
But they didn't. They just ignored me. I felt insignificant, invisible. I longed for the security of my old office, with the comfort and control it gave me. Here, I felt like a fish flapping on the shore.
How do you handle other people's kids? Were you allowed to tap them on the shoulder? Hold their hand? Ruffle their hair? Give them a sly dig in the ribs if they got out of hand?
Well, you don't handle them for a start, I imagined. That would breach all health and safety and morality rules, wouldn't it?
Treat them like employees, I thought. Be polite but firm. Don't get too close. Don't take any nonsense.
And then....thwack! I was punched so hard in my nether regions I thought I was going to be sick. I looked down through watery eyes to see a five year-old boy with floppy hair, grinning like a Cheshire cat as he held his clenched fist towards my face.
"What the...!" I exclaimed, biting my tongue to prevent me finishing the phrase.
"You're Sam's dad, aren't you?"
Thwack again. And again. And then a shower of thwacks splattered against my lower body, like missiles from a paintball gun.
"GET HIIIIIIIM!" a quartet of bovver boys yelled. At their lead was my four-year-old son.
I love fighting with my sons. When I used to get home from work, they'd be on me like chimps on a bunch of bananas, wrestle me to to the ground, then use my body as a trampoline, until I swiped them away with a wave of my arm.
They'd attack and retreat, attack and retreat, until it ended in tears. It always ended in tears.
But it didn't matter: they were learning how to rough and tumble in the safe knowledge that their giant dad would never hurt them.
The downside was that my youngest son took this to mean that he could attack me at will in any situation. And he'd clearly told his classmates that I was game meat, too.
'"Boys, boys, BOYS!" I voiced, nervously, covering my gonads to protect them from razor sharp fists.
The mothers looked across, blinked, and looked away. Thankfully, my son's teacher intervened, clapping her hands and shaping her face into a picture of stern intolerance. The boys retreated, like chastised pups.
"This is going to be hell on earth," I thought to myself, eyeing the other people's kids. Half-pint strangers.
My son took my hand and looked at me as if to say: "Don't worry, Dad, I'll look after you."
With order restored, we were organised into our groups. I was in charge of five kids - my son, two girls and two boys. It was a great system. I'd wondered how they were going to get 30 kids from one half of London to the other, by roads and rail, without losing one of them, but by making each parent responsible for a small group, it suddenly made the task less onerous.
The teacher led us through the gates and out into the big wide world of the open street. I was towards the back of the snake and suddenly found myself in my element, ordering, cajoling, controlling my little team of little 'uns. I hadn't had this much control since I lost my job seven months previously.
"Stop that. Stop this. Stand here. Stay there. Don't do that. Keep away from the road. AND STOP PULLING ELEANOR'S HAIR!"
Eleanor started to cry, her tiny face crumpling into a mush of sadness. I wanted to comfort her and she reached for my hand. But I couldn't take it. I was holding my son's.
Besides, I didn't know if it was allowed. You read about teachers being banned from cuddling crying children these days. Surely I'd be called a Paedo and kicked off the train if I attempted to console another parent's child?
After a few minutes, Eleanor's tears dried up, but she was still upset. If she'd been my own, I'd have taken her into my arms, stroked her hair and made everything OK. But she wasn't, and I couldn't. She'd just have to get over it and cope on her own.
At our destination, we got off the train and negotiated a 15 minute walk across three busy roads and through one of London's busiest shopping precincts.
The place was packed with single-minded adults, focused on their destinations, oblivious to the train of children below their eyeline and beneath their feet.
The kids were bumped and barged, knocked and scraped. I held my son's hand tighter. He looked up at me and smiled, and touched his cheek against my sleeve.
Ahead of me, little Eleanor looked like a frightened rabbit, holding for dear life the hand of the classmate who'd made her cry, as she tried to weave through a forest of indifferent adult legs.
Then as we walked past a newsagent's, something caught my attention. A fading yellow poster was peeling from the inside of the window. On it was the face of a little girl who has become the most familiar face in Britain. Madeleine McCann went missing in May 2007. She was three years old. The poster said: "Look into my eyes."
As I did, she reminded me of the upset little girl, the daughter of another parent, who was now in my charge. And I felt an overwhelming wave of protectiveness.
These kids were my responsibilty: it was my job to keep them safe. It didn't matter that they were other people's kids. They needed me.
I saw a young bloke bouncing along the pavement with iPod headphones in his ears. All that mattered was his destination.
He had a 'get-outta-my-way-I'm-coming-through-I-don't-give-a-flying-f**-how-small-you-are' look on his snarling face.
He was heading straight for Eleanor - and then he barged straight into her, knocking her off balance. I let go of my son's hand, and pounced towards the youth, grabbed his shoulder and spun him to face me.
"Excuse, sir, please would you pay attention to where you are walking, there are little ones around," I said, though it might not have come out quite so politely.
And then I felt a tug at my sleeve. Saw in my sideways vision the figure of a small person.
It was Eleanor, looking up at me with big brown pleading eyes, as if to say, "Don't do it. He's not worth it," when in fact she shouted: "SAM'S DAD....I NEED A WEEEEEEEEEEE!"
The youth laughed, and I smiled, and I forgot all about 'elf and safety and don't-touch-children-or-you'll-be-branded-a-paedo regulations. I scooped Eleanor up in my arms, ran along the snake of children to the front of the queue, and handed the little girl to her teacher.
"Here you go," I said. "I'm not qualified for THIS part of the job."
I turned back to find my place in the line, and to my little group of dependents. Another parent's daughter reached her hand towards mine, clearly impressed by my heroics with Eleanor!
"Sam's dad: can I hold your hand?" she said.
But it was too late. My son had already beaten her to it.
Are you nervous of other people's children?