Paul, I suspect that the "loss of intensity" is that the spark becomes intermittent. With the engine running at 2-3,000 rpm you can't see individual sparks, it looks like a continuous spark. In other words, your problem now might be ignition failure.
I suggest you disconnect the kill wire at the ignition module, checking the module's grounding and the gap between module and flywheel while you are at it. Then repeat the test with the in-line tester. If none of that makes any difference, it will be time to check the module's primary and secondary resistance, and/or look for a spare module.
