The consensus estimate for Apple's (NASDAQ:AAPL) fiscal 2014 second-quarter iPhone shipments is 38 million units. But Morgan Stanley analyst Katy Huberty's AlphaWise survey estimates Apple will sell 42 million iPhones. This 4 million unit difference in estimates shouldn't be ignored -- especially since Huberty's AlphaWise survey has proved to be more accurate than consensus estimates.

Making the matter more intriguing, 4 million additional iPhone sales could push Apple into blowout territory, a place Apple definitely didn't reach in Q1. As Apple's most profitable segment, 4 million incremental iPhone sales could play a big role in Apple's bottom line, helping the company easily post two quarters of EPS growth in a row.

Fool contributor Daniel Sparks takes a closer look at Huberty's estimate, and the implications for investors in the video below.

If you're interested in getting exclusive, unfiltered access to Motley Fool co-founder and CEO Tom Gardner's personal "Everlasting Portfolio" of stock picks -- a portfolio that's outperformed a stunning 99.6% of similar mutual funds over the past 12 months -- you're in luck. For a limited time only, Tom is inviting new members to apply for "early acceptance" into The Motley Fool's crown-jewel service -- Motley Fool ONE. If you're accepted, you'll be invited to test-drive Motley Fool ONE with zero risk or obligation for an entire 365 days. Simply click here to apply now... time is running out!

This article represents the opinion of the writer, who may disagree with the “official” recommendation position of a Motley Fool premium advisory service. We’re motley! Questioning an investing thesis -- even one of our own -- helps us all think critically about investing and make decisions that help us become smarter, happier, and richer.