Fourthmeal adherents still bruised from the aftershocks of allegedly diminished meat content in Taco Bell’s beef offerings received a transfusion on March 8 with what the firm described as the largest product launch in its history. In an attempt to revive sluggish sales, the Shangri-la of late-night food plunked down a $75-million advertising bet on the 1 a.m. foodie’s idea of manna: Doritos Locos Tacos.

The concept is simple: Bake a giant Nacho Cheese Dorito into the shape of a hard shell and fill it with lettuce, shredded cheese and beef-flavored meat substance. Product tests in three cities last spring played so well with the Mexican-style fast food crowd that Taco Bell actually announced plans to launch a Cool Ranch version of the “crazy” taco this fall. There was never a question that the idea could fail. Expectations rode high. Of course, this is how most trips to Taco Bell start.

An initial attempt to sit down and review the gourmet qualities of Doritos Locos Tacos at the State Street location in Madison yielded even higher expectations – all the shells were sold out by the witching hour on a Friday night. A second attempt a week later, at a location in Indiana, finally resulted in success. The taste test would be conducted in the ideal setting for T-Bell: the back seat of a car on a long trip to Florida.

Visually, the taco is initially stunning. It is ensconced within a bright orange, heavy-paper taco lookalike. Peeling back the protective layer reveals a slightly less iridescent, but no less impressive, orange-dusted shell. The geniuses at Taco Bell labs had succeeded! Even the tactile experience was a triumph, a certain spongy hardness imbued into the shell-shaped Dorito. It was in that faithful representation of the chip that the Locos Tacos fail.

The tastes and tongue-feel of the experience simply do not mesh. There is a certain softness inherent in a Dorito chip that lacks the crunch of a successful hard shell, bringing on thoughts of staleness. The one saving grace that was expected, given the copious amounts of cheese powder, did not even show hints of showing up in the meal. Instead, the shell tastes simply like a regular hard taco shell. Disappointment grew as the second taco met taste buds, and was abated only by the nectar of the custom Mountain Dew variant, Baja Blast.

Taco Bell did not fail in implementation. Rather, the letdown sprang from imaginations of late-night eaters everywhere, a potent reminder that just because something sounds good does not mean it is good. Doritos Locos Tacos are not machinations; they simply just do not belong. At least before bar time.