Why Dunkin doesn't have a Donut in its logo?

Dunkin knows its specialty. And we all know it too. The wonder breakfast Donuts. The sweet donuts is not just their specialty, but a strong differentiator as well. And if donuts is the story behind Dunkin Donuts then where are the the Donuts in its logo? Why are they hiding? 

The story dates back in 2000, when the company discovered that more than 63% of their revenue was coming from beverages and not the donuts. Also that Dunkin Donuts where ranked high in Customer Loyality than its competitors - Starbucks and McDonalds. Dunkin wanted a strategy to not only retain their specialty but also pursue their opportunity in beverages market space. And then came the beverage cup in Dunkin's logo. 

Now take a moment to think, does a shift from Speciality to Mainstream in order to capture more business, a right move for any company such as Dunkin Donuts? This is what GM did with Cadilac which stood for luxury by making it cheaper and introducing new mediocre models that delivered a cheap luxury which eventually failed Cadillac and GM. A mixed brand confuses its customers. Psychology says Luxury is not Cheap.

Jack Trout in his book "Big Brands, Big Trouble", shares a variety of examples where companies have failed in making such shifts and have never been able to bounce back. Jack advises to stick with established specialty, avoid being mediocre in the mainstream. Though, it has not been the case with Dunkin Donuts for Dunkin retained "Donuts" in its name to deliver specialty and its 

I'm not sure if the Cup in the logo must have helped Dunkin Donuts to sell more beverages, but I'm sure it has the potential to confuses its audience.