Hey gdl203, imagine tying one with no dimple and then pinching the bottom of the knot so it bumps outward. I tried tying one just now like that myself to snap a pic of but I couldn't do it! I guess dimples are unavoidable b/c of my left handed freakishness or I just need practice (Not that I will, I don't like the way it looks anyway.)
Perhaps what I've seen are the double dimple but with the dimples on the sides so small that I haven't noticed them. What is noticeable is the prominent bulge outward in the middle by pinching.
I don't know what the correct name for it is, or if there even is one, but I saw one site describe it as "thrust" and liked that term.
A description from this site
Personally, I have to wonder why you would want the dimple at all, from a dress-for-success standpoint. You rarely see the dimple at the CEO level, where they favor the forward thrust of the lower part of the knot. My guess is that when they see the dimple in their mirror in the morning, they stick their thumb up under the back of the knot and push it out. Nice and assertive.