Strength of the strapping buckle

We were wondering just how strong the straps buckle is.  How does it compare to tying a knot?  We had our local tension testing facility pull some straps with buckles of various types.  Here is what we found:

straps buckle testingcordstrap buckle testingdestructive buckle test

 

Woven cord straps buckle averaged 60% joint efficiency

Composite cord strap buckle averaged 75% joint efficiency

Ladder style straps buckle averaged 90% joint efficiency