Two weeks ago, I was cycling home after visiting my 90-year-old father who had fallen over and broken a hip. It was a fine spring evening, my bike had just been tuned up and I was racing along feeling grateful not to be ancient, frail and immobilised.
Halfway down Dalston Lane, the hipster cycling in front of me took a corner too fast, lost control of his bike and fell under my front wheel. I panicked, swerved and fell off myself.
As I lay on the tarmac, I had a sense of deja vu. The first thought that came into my head was: I've had a bike accident - again.
Readers of this column might be getting a sense of deja vu too. It's not the first time they have had to read about me falling off my favourite means of transport. When I presented myself at work the next day, a colleague took one look at my arm, hanging feebly in a sling, and said: "How annoying! You can't even turn it into a column, as you've written that one already."
At the time, I agreed. But two weeks on, I've changed my mind. This time, it's different. My father's broken hip and my own broken arm have taught me two lessons in how to get more done that are so profound, I have a duty to share them.
When I came off my bike last year, I landed on my face, got a black eye, and grazes and bruises on my forehead, cheek and chin. The subject of the column I wrote then was how to pretend to be a professional woman when you look like the victim of domestic abuse. That article now strikes me as being of niche interest - although I did receive an e-mail from a woman who had come off her bike, lost seven teeth, and gone into the office the next day to chair a meeting.
This time, what I've learnt is of wider appeal. The two fractures establish two counterintuitive laws of productivity that can be used by anyone.
The first law I have invented myself and it goes like this: If you slow technology down, you go faster.
I have a small break at the top of my right arm, which means I can move my fingers and wrist, but the arm is strapped up so I can type only very slowly. Instead of being a disaster for someone who spends the whole day at the keyboard, it has made me write more efficiently than I've done in years.
Because typing is hard, I am having to practise the long-forgotten skill of thinking before I write - a requirement in the days of the manual typewriter, when the strictures of the Tipp-Ex bottle meant getting it right first time. Now, thanks to my computer's infinite tolerance of mistakes, I think nothing of getting it wrong 20 times before finally getting a grip and writing something intelligible.
While my right hand is just about up to typing, operating a mouse is too much, and I've had to pass the job to my left hand - which is entirely unequal to it. I now find that clicking on anything at all makes me feel like a contestant in The Golden Shot, the 1970s television game in which a blindfolded cameraman holding a crossbow was guided by a contestant on where to aim it: up a little. Stop. Left a little. Stop. Up a little... Getting the dratted cursor in the right position is so arduous that multitasking has lost all appeal. There is no temptation to spend the day flitting from e-mail to Twitter to eBay and back. I've had to pick a task and stick to it.
I have discovered these joys the hard way, but I don't see why they couldn't be enjoyed without falling off a bike. Anyone can operate the mouse on the wrong side - although I should warn them that the learning curve is so steep that it took a few days for my left hand to get the hang of it, sending productivity tanking.
A more permanent solution is needed. Hardware manufacturers should set out to produce cumbersome technology for offices - anti-ergonomic keyboards and mice that are as hard to control as supermarket trolleys - making us masters of our computers once again, rather than vice versa.
The second counterintuitive law of productivity is not entirely my own invention. C. Northcote Parkinson was the first to notice the indisputable truth that work expands to fill the time available. But in the past few days, I have been shrinking time so drastically, often downing tools at 4pm to go to see my father, that I am starting to wonder if Parkinson went far enough. If you reduce your hours at work, not only do you achieve the same amount, but you may also achieve more.
What I can do when I'm on a roll for four hours is greater than what I can do in 10 when I'm not on one.
Again, you don't need a father with a broken hip to be spurred into bouts of intense work. We just need something - anything - in our lives with a more urgent claim on our time than work to make us whip through the tasks in a jiffy.
THE FINANCIAL TIMES