So I used to have the time to watch all the vlogbrothers videos all the time; then I got extremely busy and had no time to do anything extra. I've been able to rejoin the regular watching of Youtube, but I feel like I've missed something. Namely, why the dooblydoo is not being called the dooblydoo anymore... I've noticed people have commented that "He almost said dooblydoo" but I've never gotten an answer as to why.
He called it the Dooblydoo in this video just last month; there just hasn't really been anything in the dooblydoo.
On Crash Course he doesn't call it the Dooblydoo, probably so as not to confuse CC viewers that are only partially made of awesome and wouldn't get the reference.