I've come to the conclusion that any serious marketing training course should include sitting around cable TV to watch a few old episodes of Bewitched.

Remember how Darren Stevens would be working away on a great campaign at the ad agency and then a magic spell would mess it all up by turning the client into a chimp or something? That's exactly what it feels like to be a marketer in the wonderful, ultra-measurable, Internet-age.

Last week an SVP of marketing for a very well known company, who I personally have admired for years, sent me a note turning down my invitation to speak at our upcoming Subscriptions Summit.

He explained, "We recently found there is a glitch in our ecommerce system and thus all marketing tests from the past have to be thrown out and redone. i.e. What we think we learned from tests is all in question because of system failures that lost orders.

Therefore, when I imagine what a group of my marketing peers would ask me on stage, I would feel like a phony trying to answer on this subject."

When I read that, a big pile of guilt slid off my shoulders. Our marketing tech isn't perfect either. We never measure everything I think we should - nor do we always have the time to pay attention to the results properly.

But I guess that's condition normal for marketers these days. Tech SNAFUs are inevitable, and you can't guilt yourself out for not being perfect all the time. I guess it's just about doing our best and not letting that magic chimp thing bother us too much.