I'm not sure what the phrasing of the reporting has to do with anything. It's an effect not a cause. The pressure from Wall Street is due to, well, the pressure from Wall Street. If analysts on Wall Street form a consensus around a company's expected earnings, then the market will price in that consensus. If that consensus turns out to be wrong, the market will (in theory) adjust accordingly.
In other words, if analysts are (in retrospect) over-optimistic, the stock temporarily becomes mis-priced and expensive (relative to an unknowable reality at the time) until the earnings report. Usually these analysts' look to the company's guidance (edit: or in google's case, the lack thereof) in forming their valuation. Add it all up and it's hard to see how there is pressure on a company to beat expectations, since they have the ability to set conservative guidance and try to get analysts to come to a consensus that is in line with the numbers that actually come up. If the company is performing poorly, they either depress the stock price in advance (under promise, over deliver) or later (over promise, under deliver) but regardless of when this happens if you buy into the EMH the stock is always trading at the proper value, behavioral economics notwithstanding.
For an example of an exception to this rule, see AAPL which routinely beats estimates yet sells off. One theory is that there is such latent fear that Apple is losing its mojo, each earnings report is a reminder that their growth doesn't compare to the old days, so investors flee despite their return on capital being extremely competitive.
In other words, if analysts are (in retrospect) over-optimistic, the stock temporarily becomes mis-priced and expensive (relative to an unknowable reality at the time) until the earnings report. Usually these analysts' look to the company's guidance (edit: or in google's case, the lack thereof) in forming their valuation. Add it all up and it's hard to see how there is pressure on a company to beat expectations, since they have the ability to set conservative guidance and try to get analysts to come to a consensus that is in line with the numbers that actually come up. If the company is performing poorly, they either depress the stock price in advance (under promise, over deliver) or later (over promise, under deliver) but regardless of when this happens if you buy into the EMH the stock is always trading at the proper value, behavioral economics notwithstanding.
For an example of an exception to this rule, see AAPL which routinely beats estimates yet sells off. One theory is that there is such latent fear that Apple is losing its mojo, each earnings report is a reminder that their growth doesn't compare to the old days, so investors flee despite their return on capital being extremely competitive.