George Reyes, the 50-year-old in charge of Google’s accounts, might not have run the finance department of a public company before, but surely he would have been aware that loose talk can cost stock-market investors billions.

So it proved this week. On Tuesday, just a few words on how Mr Reyes expects Google’s stellar revenue growth rates to fall were enough to knock $8 billion (£4.5bn) off the company's market value as the shares plunged just minutes after his speech.

"At the end of the day, growth will slow," he said in a presentation to analysts, bankers and journalists that was also broadcast on the internet. "Will it be precipitous? I doubt it."

The remarks – identified as "remarkably frank" on Wall Street and made only two days before Google is to host its annual analyst conference in Silicon Valley – sparked a frenzy.

In morning trade in New York on Wednesday, shares in Google rose just $1.10 to $363.72, regaining some poise – but just a fraction of the $27.76 they lost in the previous session.

Amid the losses and finger pointing, Google will be feeling uneasy. The company has been criticised in the past for failing to make forecasts on forward revenues. But suddenly the problem was that of too much information. Moreover, Mr Reyes was flooding negative comments into a nervous market on a day where a lacklustre set of US economic data had already given the session a bearish tone.

Traders did not know what to make of it. To an uninterested passer-by, Mr Reyes's comments might seem unremarkable, but frank opinion from Google is something of an unknown entity.

In the aftermath, it will not have helped that, of all people, Henry Blodget was prepared to criticise, of all things, Google's information-handling skills

Mr Blodget, a former star analyst who became famous – and then infamous – during the dot-com boom for his optimistic stance on internet stocks, argued that Google gaffed. He suggested on his blog that shareholders had been let down by the way the "news" that Google cannot maintain its red-hot revenue expansion was "unintentionally" fed to the market.

"Even the company would probably agree that, webcast or no, today's media and market cyclone was not the ideal way to share new information with thousands of shareholders," he said.

Mr Blodget might have been banned from the securities industry for life, but that such opinions are floating around even the periphery of Wall Street is embarrassing for both Mr Reyes personally and Google as a company.

There have already been suggestions that Google’s outside appearance as a slick, well-oiled internet pioneer belies a company that suffers from serious disorganisation under the surface. One senior Google figure recently told Times Online that the culture inside the company regularly descended into "confusion".

To clear up just such confusion, Google was forced to release a "clarification" of Mr Reyes's remarks. However, it still had to admit that "our revenue growth rate has generally declined over time and we expect that it will continue to do so as a result of the difficulty of maintaining growth rates on a percentage basis as our revenues increase to higher levels".

For the most part, analysts asked themselves whether this was anything we didn’t already know.

The consensus looked to point towards "probably not". Analysts could not help agreeing with Mr Reyes's basic point – that big companies cannot grow as quickly in percentage terms as small ones, an observation grandly dubbed "the law of large numbers".

As Ed Stenson and Jon Lewis at Schaeffer’s Research said: "Unless investors imagine that extraterrestrials are going to be using the search engine soon, the kind of growth rates we’ve seen recently have got to slow down."

And as Philip Remek at Guzman and Company pointed out, the crucial question for those riding the Google rollarcoaster is the pace of the company's deceleration. The stock, which rose more than fourfold from its August 2004 public offering to an intraday high above $475 in mid-January, has now lost more than a quarter of its value.

Amid such volatility and momentum, a few words can have a big impact. If George Reyes didn't already know that, he does now.

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