"What is this product called? Sounds good. I've often wondered about mixing gravel in a mixer with a watered down glue for problem areas. Bark in windy areas is also an issue - could this be a solution here?"
"Pilot hole through timber with larger bore to follow. Slot in and off you go, happy days. The Timberlok equivalent imo.
As for the thread cutting through the timber - not at 4''/100mm x 100mm timber in my experience :->
"Never used those but don't you need a larger "clearance" hole for the bolt to pass through the wood otherwise I would have thought it would cut a thread in the wood and not be able to pull it down tight?