For my 4wt silk line I use loop to loop connection to the furled leader to line connection and loop to loop for tippet. I do use a piece of 4x tippet about 12" long and then 18"+ of lighter tippet.
For a plastic line, 5wt or so, I nail knoat a piece of 6" mono to the fly line and then connect to furled leader with loops as above. Works very well this way for me.
Pete