Depends on you. If you know how to launch unhooked and have you lines set to be fully depowered with the strap pulled in, then yes it is a good option but can only be done with chicken loop alla classico.
If you use a lock in release system with no CL then it is difficult.
If you launch hooked in keep 1 hand on your release activator at all times till you are safely in the juice.
It is advised to launch unhooked as if anything happens - jus let go.
ALWAYS LAUNCH UNHOOKED unless you are on snow or in water.
P.S., In the early days nobody even dared to permanently connect himself/herself to the kite as Bruno suggested in his 4 line kite patent. Then I introduced the Chicken Loop allowing one to connect/disconnect from the kite as will, http://groups.yahoo.com/group/kitesurf/message/4358 . Since then, all kite manufacturers standardized on the chicken loop. Many have used the the chicken loop and some has found enough confident to connect themselves permanently to the kite even when launching or riding near hard objects. MANY HAS DIED OR INJURED (including some I know personally)! So learn from their mistakes or...
arn't you at full power (in terms of bar position) when unhooked...therefore it seems kinda dangerous as one could get stretched out if to much power is there...now if you let go the kite may or may not depower...i've seen alot of kite ditchings go bad...for me it always made more sense to hook in so i can control the power...not trying to start any shit with anybody...just my 2 cents.
p.s. if you use a shackle don't shackle in until your kite feels managable
true "full depower" is the strap pulled in and bar pushed out
another point if i may...
what about in light/gusty winds...there you are at full power(if your un-hooked), the kite is at the edge of the window and a lull/gust comes...now if u want more/less power u have 2 play with the strap where as if your hooked in just move the bar.
Very true window man but not when you are unhooked as you cant change the relative length between front and back lines.
Therefore full depower whilst unhooked is with the strap in and unless you have a spinlock or something like wrapping the depower around the bar when its fully sheeted out but thats too much messin for me.
And sure, each method has its pro's and cons. Personally I am hooked in with hand on release mech but have coinsidered changing for some time.
I haven't seen anyone killed kiteboarding, then again I have researched all that I have heard about. In several of these cases the rider likely wouldn't have even been injured much less killed if he had launched or landed "unhooked." Then there have been many serious dragging and lofting accidents that were survived and approximately 50% or more might have avoided injury IF they launch or landed unhooked. Will tons of kiteboarders be maimed and killed for NOT launching and landing unhooked, likely not. Only some riders will, as time and experience have established, volunteers?
So, it is just another choice for kiteboarders. Do your homework, think about it and choose well.
Another option to launching unhooked that might be more acceptable to more kiteboarders would be some form of reliable and safe automatic kite depowering device or AKD. There was a good thread going on this but it was lost in the crash. I have some of the sketches at home and will start a new thread.