Over the last three weeks, I have had as many conversation with senior executives about how they can cope with the constant barrage of incoming information, mainly via email.

In various lengths of windedness, I tell them rather smugly that my inbox is empty 95% of the time. Not because no one ever sends me anything (although that may well be true) or that I just delete it, but because since January 2008 I’ve followed David Allen’s Getting Things Done (GTD) system.

Now I don’t know why it works for me. Maybe it appeals to the left side of my brain, maybe I just like process, or maybe it just works. But I highly recommend it to any senior executive whose inboxes control them rather than the other way around. If they can get it working (and you do need to work at it for a couple of months) I can guarantee they will feel more productive, less stressed and more in control.

In fact, I think there’s such a big internal market for this I’m considering offering one-on-one coaching to H&K’s elite.

A few different projects have got my mind focused on influence this week. The first is planning the research design for the centrepiece of my book on social media in B2B (can we measure the influence that social media platforms have on the different staging of the B2B buying cycle?). The second is connected with our cooperation next month with Twitter at the Cannes Lions.

In both contexts I am reaching the conclusion that influence cannot be measured, and thus is a futile metric for exploration. Sure, you can ask people how much influence something has or has had, but do they really know? And what is influence anyway? In my mind it is a power that makes someone do something, not a property that any individual possesses. Invariably when an individual does have influence, it is only over a specific thing. Even the most influential people in the world (politicians, one could argue) have no influence over whether I will buy a Sony or a Panasonic television this weekend.

In a public environment, you might (just) be able to attempt to measure influence by looking at people’s networks, the re-communication of their utterances, but to me this is just reach. Someone who says something that reaches 100,000 people is no more influential than someone who reaches just 100, if all of the latter act on that communication but none of the former do.

In short, influence needs to be measured in context and at the receiving end not the transmitting end. That is not something you can do by looking at their blog posts, tweets or Facebook profile.

So do we continue to try and measure things that cannot be measured, or do we measure things that can be measured and can give us as marketers comparisons that we understand.

I think it’s the latter.