I process the world visually. Using Howard Gardner's theory of multiple intelligences, I'm very verbal/linguistic and visual. I see words in my head. When I'm trying to remember notes I've taken, I can see the page in my head, along with where on that page the particular notes are that I'm trying to remember. Not quite a photographic memory.
People are names to me. Stacy is S-T-A-C-Y. I picture the letters, not her face, when I think of her. And so on.
It should be no surprise, then, that whenever I use the ultra-cool tool, twhirl, I see it as t-whirl (two syllables and everything). I bet that it's meant to be one syllable as in "twirl," but I see the word "whirl," and the "t" just happens to be in front of it.
Usually the only way I can get past such a thing is to say it out loud. So if you run into me quietly muttering, "T-whirl, t-whirl, t-whirl, twhirl...." you'll understand why.