TKN...
Totally agree with your summary, very well stated.
However, I don't quite get the body of your post.
If you mean that a Basic 4x4 Recovery Kit should have 9,000 Kg rated shackles to have a "balanced" recovery kit then I am of the opinion you are wrong but then I also possibly don't know what you mean by "balanced". If I do understand what you mean then to infer that a Kit such as DX grunt linked up from Nobles that has 3.2 Tonne shackles yet 12 tonne Starps is not "balanced" is totally incorrect.
As a point of interest the design factor for rating Shackles, Slings and Chains varies slightly from 6 to (where people are in the loop) 8 or 800% if you prefer. I totally agree no-one should use ANY powered or mechanical recovery equipment without understanding what they are doing however while anyone can walk in off the street and buy the gear that will never happen. The entire objective of safe recover techniques is to educate people on understanding and interpreting equipment WLL's, calculating the forces being applied and rig the recovery appropriately.
There will always be a lowest common denominator effect in any rigging that determines the safe WLL of the recovery or situation. It might be the line pull of a winch, the shackles whatever BUT a lot of the time the weakest link is the dumbass human.
I also would guestimate (having never seen one that big) that a 9 tonne rated Bow Shackle will weigh approx 3 Kilo's and cost at least $60 each and that the pin will be well over 30mm in dia so (as Bigrig also says) it will not fit many, if any 4WD recovery points, billet hitch or winch fitting which severely limits where you can use them anyway.
For reference the largest shackle I use at work rigging moorings for undersea equipment is 8.5 tonnes rated and is goddam huge. I can get them for nothing but still wouldn't bother to carry one as I cannot concieve where I would use it.
Bottom line ? ... for Joe Average with a Basic Recovery Kit and esp with no winch then 9 ton or higher rated shackles are not practical or affordable.
However any debate on the subject is healthy and each to their own opinions. I will totally agree that always erring on the high side and "if in doubt, DON'T" is the way to go...
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