I use a loop to loop (perfection on both) for Leader>Tippet so I don't eat up my leader replacing tippets. A leader usually lasts me a whole season.
I use a Davy knot (figure 8) for small fly's, and a NS Loop for larger fly's (#12+) and streamers.
I never fish droppers but if I did I'd do it like Al does, or I'd whip a dropper loop into the leader above my tippet loop...and loop to loop another short tippet onto it.
Tying to the bend always seemed like a stupid idea to me, but a ton of guys do just fine with that system so whadowyno.
A truly GOOD way to dropper a fly doesn't exist IMO, so that's why I never do it.