I know I don’t look old enough but this summer will mark my thirty years in the City of London.

It was back in 1988 that I first stepped on to the trading floor of Kleinwort Benson at 20 Fenchurch Street and I’d like to think that that day was the start of a steep learning curve. A curve which I’m still on, by the way.

One of the early lessons that senior traders, and then more latterly senior journalists, tried to teach me was how to spot a rat. Rats come in various shapes and sizes but one’s ability to spot one early enough to act upon does tend to ensure longevity in the cut throat Square Mile.

From Nick Leeson blowing up Barings to Marconi’s slow-motion car crash, from Iceland becoming the world’s most dangerous hedge fund to cryptocurrencies, some impending disasters are easier to spot than others.

Of course I’m not pretending to have either dealt perfectly upon all of these hiccups in the early days or shown great reporting prescience more latterly every time a rat comes along, but sometimes you just can’t fail to get a win.

I can tell you straight away the best and worst thing about my current job. The worst is going to bed before your five-year-old daughter at circa 7 p.m. so you can get up in the middle of the night five days a week. The best, however, is the fact that repeat dumb behavior by markets and certain participants hands out several freebies a year that will always make you look smarter than the average bear.

Take this month’s Argentina blow up for example. When a country which has had more debt blowouts than I’ve had bottles of Malbec — and that is a significant number I can assure you — is issuing 100-year paper at sub-8 percent yields, as it was last summer, you know you only have to wait for the inevitable to happen before being proved right.

When investors can’t help themselves but hoover up vast quantities of the likes of Snap or Go Pro at IPO (initial public offering), regardless of the actual proven fundamentals you know you pretty much just ride out the “you just don’t get tech do you Steve” bull and wait for the quarterly reports to come in over the months ahead.

So, at the moment what are some of the no brainers out there?

Well there is the perennial joke that is the Italian debt market, propped up by a central bank so terrified of letting markets decide on another shambles of a political situation. Elsewhere, there’s an extension of the Argentina trade, otherwise known as “is this the moment the hedge fund hotel check out” gets jammed as people finally look at the current account deficit debacle of a host of emerging market countries?

Other favorites include pretty much any company that thinks it can “do an Amazon” and never actually make money until it has attained global domination … I mean greater market share.

Guess what? You can’t all be Amazon and one day soon the market will suss that.

Still, the repeat stupidity, greed and plain gullibility of the herd will hopefully keep me in business for the next thirty years.

(Editor’s note: Both Snap and Go Pro were not immediately available for comment when contacted by CNBC.)

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