As Chris described, the main issue was concussion and career ending injury, or IOW the issue was crappy training due to crappy criteria.
I've said for over a decade that the only way to make it safe was to CHANGE THE CRITERIA. Shorten the contact patch drastically (or reverse it), then if your dog has even a toenail in the contact area BEFORE the teeter touches ground, your dog faulted the obstacle. This enforces HANDLING and TRAINING of the obstacle. Dog must handle the teeter safely, tipping it in a reasonable manner, before they may leave the obstacle without fault. Tada! No more flyoffs, no more having to screw around with weights to deal with different weight dogs. Just a safe but fun obstacle. IMNSHO. :-)
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