notice in my orginal post I said find two trees or tree and side of building etc. to mount your hooks.  Obviously you got to think it thru and get advice from someone who builds stuff.... but it is not rocket science.

Funny how you say you dont trust non commercial yet you go bounding around on stilts with your head way above what the lord your maker intended LOL.

Geez..... you dudes are lucky. Due to fear of lawyers there is not a school gym in the US that would let you do any self training...... or any stilting of any kind for that matter.  Most school gyms don't even own landing mats or crash mats (now called skill cushions again out of fear of lawyers). They are afraid if they have a mat a kid will try something then they will get sued cause the kid was too stupid to realize you can still get hurt on mats.

correct they would slow your fall and playing with tension could aid in back flips.  Front flips are tricky in belt though.

Bungee is amazing stuff..... the better actual bungee cord; over surgical tubing, can be bought by the roll at Home Depot etc.  

The gymnastic applications we used them most was for learning lock arm giant skills on Men's Rings and some in Acro Gymnastics for the bases top in Tempo Skills.  Someone got the idea of the commercial application over the trampoline for amateur play and whala... thats all you see of them now.

They are not used in gymnastic sports at all except maybe to play.  Certainly are not used in the trampoline sports. They are not that effective except for some basic stuff that is more easily spotted other ways.  Those other ways (unless you have a coach and training facility) are not as much an option in this case which is why I brought it up.

Bungee is amazing stuff..... the better actual bungee cord; over surgical tubing, can be bought by the roll at Home Depot etc.  

I would agree with you that a tradidional spotting rig with an EXPERIENCED spotter at the end of the ropes is best.  Use what ya got though.

Im a US dude.  Long time gymnast. Mostly bought a pair of jump stilts  to bounce around town to promote my businesss.  (Trampoline and Acrobatic school). Not sure if I'll make the papers as an article of a local crazy man or a police blotter about hauling me off to the hospital:D

Just throwing this idea out there for ya'll to ponder.

Long ago a dude invented the Bab System for teaching gymnastic skills.  Basically its bungee jumping with a bungee on each side of you. 

 

Pic a tree and a tree, Tree and balcony, etc etc.  Get some surgical tubeing.  Tie them off so that the tension would prevent your head form hitting the ground even if you dove to a handstand.  Willl take several tubes in a bundle most likely.  Right tension Im guessing would be about the same as it holding you just off the ground W/OUT stilts on. But that is just a guess!!!!. 

Build you a belt.  Mountain climbing harness? safety construction worker harness?  order a gymnastic spotting belt?

Then put on your slits.  Lean against tree/building etc.  You might have to put a rope onto the belt to tug it down. secure rope with a clip to belt but tie off the end to something low out of the way.  Put on belt.  Relase tug down rope from belt and pitch it off to the side.

JUMP AWAY.  Test out the safety range of the bungee cord.

Do a lot of experementing of the range of motion of things before you start going full tilt.

. Wear a helmet AT LEAST. 
. USE AT YOUR OWN RISK!!! 
. Assume Im full of SHIAT and trust nothing I say
. Fully test it out (put your buddy in it first :p) etc.
. You assume all risk

Good luck

watched your vid pretty closely.  Good job.  My Masters  study is in Motor Learning (Biomechanics with some other stuff thrown in) and after watching you and others jump I can say for more input on this go watch some champion trampoline vids.  Slow them down however you want.  The technique is pretty much the same.  Also watch a little Double Mini trampoline. The take off onto the first part of these type of tramps is the same take off for the run hurdle punch approach you demonstrated here.

Hope my cheapo Craigslist stilts get here soon.  Imma going to kill myself trying to use em (I'm 46yrs) but Im hoping in the process Ill attract some crowds and excitment around town to get PR for the trampoline / Acrobatics and Dance school I own