I looked up the subject and found an article from a manufacturer. They say the structure is somewhat resistant because it must survive the vibration common in transport. They made no further claims.

My guess is they would need to cast angle iron into the corners that was welded to the inner rebar. Then, as the blocks came in contact, a welder would run a bead over a few feet. A small tack weld would not be strong enough.

I can think of a few cases where access to the angles would be impossible. Interesting problem.

Rick