Actual phrase is "derring-do" see http://www.merriam-webster.com/dictionary/derring-do
If you know that much about "dippety-do", you must have been an ET...way to "metro" for MM/ELT... 
Check out Broadzilla's post, I copied his "Daring do" and meant to correct him as you did me, but I forgot from all my excitement about talking about Dippety-do!

Seriously, as an aside, I went 4 months in ET "A" school (8017C) without a haircut thanks to dippety-do and Brylcreem. I had hair well over the bottom of my ears when I went off-base in civilian clothes. My military ID was always second guessed in Kenosha when I was carded, which had to be backed up with my Florida driver's liscence. I finally got busted by the Master at Arms in the Galley when I was eating MidRats. He spot frisked people for taking food to the barracks and asked me to remove my utility cover. You should have seen the coffee squirt out of his nostrils when he saw me reluctantly remove it.
Bryl-creem, a little dab'll do ya,
Use more, only if you dare,
But watch out,
The gals will all pursue ya,--
They'll love to put their fingers through your hair.
Bryl-creem, a little dab'll do ya,
Bryl-creem, you'll look so debonair.
Bryl-creem, the gals will all pursue ya,
They'll love to RUN their fingers through your hair
Oh, now there I go again. I cannot help my ex-ET self.