For investors of a nervous disposition, the past month has been torture. Some mornings I have inwardly wailed as I turned on my computer to discover another 10% wiped off the value of my portfolio. I have told myself to stay calm: a panic sell-off means the bottom is near, the market is oversold and shares are inherently cheap. Then the same thing would happen the following morning — or until the past few days.

I know what I look like in this state. Sitting on my coffee table right now is the catalogue from the Francis Bacon exhibition at Tate Britain. On its cover is a silently screaming pope in purple vestments imprisoned in what looks like a glass cage — though it could be a lift in freefall. The mouth is stretched wide and the eyes are black with terror. The expression is that of someone having several hundred volts passed through him while being forced to watch endless reruns of Big Brother.

Bacon painted this isolated pope time and again, but this one — Head VI — is the only one with an end-of-the-world feel to it. It chimes perfectly with a planet in crisis and a market in meltdown. Maybe that is what Bacon had in mind — a pope who has just heard the Vatican’s portfolio has shrunk by the odd billion and he is going to have to pull in his chasubles.

A month ago, for my sins, I said shares looked cheap — though I did add a rider. It did not seem to me that the market was yet taking the likely length and depth of the coming recession into account. Well, it is now.

At least I have not been sitting idly by. After the rescue of the banks, I decided the next sector to be targeted would be the life-assurance companies. There is a vicious circle at work here. Falling share values erode the assurers’ own capital base. They also have big holdings of corporate bonds. These, too, have been falling sharply in value.

Now, by and large, Britain’s life companies are well capitalised. I figured, though, that market sentiment would ignore that little detail and knock the shares anyway. I felt particularly at risk: my holding in Standard Life was the biggest in the portfolio. The shares had held up brilliantly over the year, but I still decided to sell — at 255p. That represented a gain of almost 20% (after costs and before dividends) over two-and-a-quarter years. I would have done a lot better to have sold a year earlier, but such is life.

For once, my timing proved spot-on. Within days, life-assurance shares had become the pariahs of the market. Standard Life fell by nearly a third. It has made only a limited recovery since.

I then decided to put the money to use in what I thought was an opportunistic manner. As a result of the Icelandic bank crash, Robert Tchenguiz, the property entrepreneur, was forced to dump his stakes in supermarket chain J Sainsbury and pubs-to-restaurants business Mitchells & Butlers. Both share prices dived.

Tchenguiz’s stake in M&B was sold at 130p — way below the then share price — which promptly brought the shares back about a sixth in two days. The Sainsbury shares fell from 315p to 267p, even though the share sale was botched and it looks as if 10% of the company remains frozen somewhere between here and Iceland.

Such a sharp fall in price, sparked by nothing more than movements on the share register, looked too good an opportunity to ignore. I paid just over 279p for the Sainsbury shares and 157p for M&B. I have made the case for the latter here on a couple of occasions, so I won’t repeat it. Suffice to say the buyer of most of the Tchenguiz stake was another billionaire, Joe Lewis, who looks to have been attracted by the group’s property pile.

Sainsbury looks very cheap. Under Sir Philip Hampton it has made a terrific recovery from the problems that beset it in the early years of the decade. The latest trading statement showed like-for-like sales rising at over 4%. The company’s “Feed your Family for a Fiver” campaign seems right for the times. Finally, the shares are trading at a small discount to the bricks-and-mortar break-up value. How can you go wrong?

My timing was certainly not perfect, for both shares dipped below my purchase price — though not by a lot. The switch has proved profitable, though I’d be prepared to buy back into Standard Life if the stock goes much lower. However, for an investor like me who puts at least half his money into value shares (the “Heaven” side of the portfolio), one is spoilt for choice at the moment. Many shares are just screaming to be bought.

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