No, I mean, it is possible to construct a statistic that is not physically meaningful.
For example, "share" is originally defined as the percentage of people (actually screens) viewing *at the time of broadcast*.
Now, how does that change with time-shifting? Say I watch within the day + 3 range usually cited. Do you count me in with those who did watch the original broadcast? Or even just in a day +3 group? Well, then there's a problem - I can be in the viewer group for multiple shows, then. Basically, the share is not a percentage. Or, if you total all the shares, they can be over 100%, which doesn't make a whole lot of sense.
There are ways to manage that, statistically, but they generally bring the measure out of the realm of making intuitive sense, and into the realm of making only mathematical sense. So, a human, seeing that share number, won't be able to intuitively tell what it means. It doesn't matter if that human is out here among us viewers, or a studio exec - studio execs are generally not statisticians, after all.
So, yeah, I am concerned that the measure no longer reflects reality in a manner that a studio exec can intuitively handle. The Neilsen organization is notorious for being slow to adapt to changes in technology, and that impacts how well the studios deliver stuff we actually *like*.