He seemed reluctant to say it and I guess that's because it's an extremely complicated topic (karma) and just cannot be summed up in a sentence. So therefore I agree that what he said was very ill advised.
Extremely complicated? The fact that there's no credible scientific evidence whatsoever for karma is perfectly simple.
Calculating the number of leprechauns a unicorn could eat is equally tricky and equally futile. We live in an amazing world, so why waste your time on imaginary poppycock?