Sorta... Malcom Gladwell didn't really pinpoint anything. He asked an ex-Pepsi product developer.
>>The difficulty with interpreting the Pepsi Challenge findings begins with the fact that they were based on what
the industry calls a sip test or a CLT (central location test). Tasters don’t drink the entire can. They take a sip
from a cup of each of the brands being tested and then make their choice. Now suppose I were to ask you to test
a soft drink a little differently. What if you were to take a case of the drink home and tell me what you think
after a few weeks? Would that change your opinion? It turns out it would. Carol Dollard, who worked for Pepsi
for many years in new-product development, says, “I’ve seen many times when the CLT will give you one
result and the home-use test will give you the exact opposite. For example, in a CLT, consumers might taste
three or four different products in a row, taking a sip or a couple sips of each. A sip is very different from sitting
and drinking a whole beverage on your own. Sometimes a sip tastes good and a whole bottle doesn’t. That’s
why home-use tests give you the best information. The user isn’t in an artificial setting. They are at home,
sitting in front of the TV, and the way they feel in that situation is the most reflective of how they will behave
when the product hits the market.”
>>Dollard says, for instance, that one of the biases in a sip test is toward sweetness: “If you only test in a sip
test, consumers will like the sweeter product. But when they have to drink a whole bottle or can, that sweetness
can get really overpowering or cloying.” Pepsi is sweeter than Coke, so right away it had a big advantage in a
sip test. Pepsi is also characterized by a citrusy flavor burst, unlike the more raisiny-vanilla taste of Coke. But
that burst tends to dissipate over the course of an entire can, and that is another reason Coke suffered by
comparison. Pepsi, in short, is a drink built to shine in a sip test. Does this mean that the Pepsi Challenge was a
fraud? Not at all. It just means that we have two different reactions to colas. We have one reaction after taking a
sip, and we have another reaction after drinking a whole can. In order to make sense of people’s cola judgments,
we need to first decide which of those two reactions most interests us.
Which is to say: essentially one guy's (informed) opinion which even he doesn't seem to commit to that strongly.
This is then followed by about two pages talking about branding/sensation-transference concluding with the punch line no one ever drinks Coca-Cola blind
The difference in flavor isn't really considered cut and dry by either of them and Gladwell focuses on branding.