FORTUNE — The last time Apple (AAPL) closed above $633 was April 9, 2012. The next day it began into a ragged six-week decline that by May 18 (the sharp dip in the middle of the chart at right) had knocked $115 off the share price and more than $100 billion off the company’s market cap.
That’s not likely to happen again, says Bullish Cross‘ Andy Zaky, and as evidence he points to what happened on July 25, the day after Apple (in a rare miss) reported earnings that were below the Street’s expectations.
“The stock tested and held the $570 level on three separate trading sessions last week after Apple missed earnings,” he wrote the next weekend. “The market completely failed to take Apple below that key support level. What’s more, the stock only closed down $15.00 from its pre-earnings price. That suggests that the bears have generally failed to take over on the momentum.
“Imagine if Apple reported a beat on earnings, gapped-up and spent three sessions attempting to take out the $620 level but failing. You would [have viewed] that as very bearish.
“The problem is this. Apple freaking missed on earnings! Missed. If a miss can’t get the ball in the bears court, then what can? That sort of mentality is what could lead to a potential parabolic move in the stock. You could see a fear driven rally which generates major momentum which could in turn lead to a parabolic move. So just keep that in mind. The risk is there.”
In July, when Zaky and everybody else thought that the next iPhone wouldn’t arrive before October, he predicted that the stock would be trading in the $700 to $750 range before the end of the year.
Now that it looks like the new phone will arrive before the end of September, he’s warning his readers that the share price could hit $700 a lot earlier than expected. His biggest fear — and apparently much of Wall Street’s — is that it’s going to get there before he has a chance to push all his chips onto the table.
That’s why it’s called a fear-driven rally.
UPDATE: Apple closed Friday at $648.11, up $11.77 (1.85%), to set yet another all-time record.