Sure havent.    I havent had a single break with a double uni and can tie in in just a few seconds so thats all I ever use.   http://www.steelheader.net/knots/double_uni.htm

Ive realized that if your very careful and make sure you dont wrap over another wrap when you pull it tight the profile is much smaller.

It's a very easy knot to tie,..but it is pretty bulky!   I'm also not sure about the strength with braid,...I worry about any knot where the braid is wrapping over the mono/fluoro like that!  Too easy for the braid to cut through the other line that way (IMO).

I'll be sticking with Alberto's knot!!
(Just found out I'll have a chance to meet Alberto himself, at a local tackle shop here this weekend if I can remember it! )

I have a little time on my hands.  If I could come visit for a month or two I'd like to meet Alberto myself and we could see about double Yaks.

why not just use flourocarbon for the whole set up

because it's expensive, heavy, and casts like he11 

and your braid hasnt rotted and i havent had any problems out of my flourocarbon and its been on the rell two months but im about to respool it

It's a world of difference in the feeling and sensitivity of using braid and a leader compared to just using straight fluro.

It is? I used to do the braid/fluoro leader thing and when I switched I don't remember losing that much. Maybe I did.  I know I didn't like having that knot or having to tie it.
I am going on 2 yrs this spring on a couple reels with flouro.  Most of my respoolin issues come from birdsnests. If  I don't have that the fluoro lasts a long time.

Maybe I will give some braid another try. I was using Suffix and other than some wind knots I liked it alright.     

why not just use flourocarbon for the whole set up

You know, awhile back it seemed like I was the only one that liked fishing with braid & a fluoro leader.   Now there's a whole bunch that fish with it while I've mainly gone back to straight fluoro on most rods,..................
Is it me or is it them?!!!!!