My method is quite similar and does not involve slamming the kite .
BOW/ Hybrid method only.....
I use it with 100% success on my 07 -08 and 09 (IDS ) Switchblades and a very similar method with an 07 Fuel which is a bit more tricky to land and not always a success.
hold kite at the edge of the wind window at about 30 -45 degrees.
pull in as much depower as you can
clip safety onto a flagging line, fifth or IDS.
hold one hand above the depower strap ( as far up as you can reach really ) and unhook from the kite. At this stage you are holding just the front lines in your hand and can lower and raise the kite with very little power in it. ( C-kites which fly more off the front lines than bow kites mean that they are still quite powered when holding the front lines AND THERFORE THIS METHOD IS NOT RECOMMENDED FOR A C-KITE )
now with the kite at about 30 -45degrees rapidly begin pulling in the front lines until you get to where they split into two about 1m from the bar now grab the upper line and continue pulling this IN .
Once you begin pulling in the front lines the kite will completely depower and begin falling leading edge down ( note it is falling not powered ) you need to be quick to pull the upper line to cause the kite to remain level as it falls...... too much and the kite will turn back up... too little and the kite will not fall leading edge flat. If the kite does flip and begin to power up you should be fine as long as you keep a good handful of the front lines if you panick your flagging line should avert any potential disaster.
Softly Lands leading edge down into the wind in 15 -35 knots everytime.
IMPORTANT : this method does require confidence and a bit of practice and should only be performed once your safety is attached to the flagging line. AS with any method I have seen it go wrong before, ( not when people are holding the front lines but more as they move onto the outer/upper front line ) for this reason it is essential that you have your kite set for flagging just in case it is required.
and practice practice practice until confident.