I've seldom needed to use the refresh button.  As far as I remember, the only case was:
When paused at a particular line, I might change some variable in the console, and click to refresh watches to immediately see the changed expression value.  We could consider auto-refreshing watches after each console evaluation.

Conceivably, a watch expression of "Math.random()" would benefit from having the refresh button, but I don't know how useful that is.  paulirish@, pfeldman@ do you know of other cases I'm missing?

I'm unfamiliar with why we need that.

Maybe kozy knows why? (Perhaps we only update watch on a few select events, but obviously not all mutations to that value).  

Pending the answer, I'm generally supportive of nuking the icon. (we could also convert it to a context menu item, basically: right-click > Refresh values)

I'm not sure that we update watches when evaluate something in console when on pause - value could be changed after evaluation.
And in case when we have some watch like "window.super_important_global_state" and would like to see changes not during stepping but after some actions in the page.

Context menu item sounds good to me.

To summarize, it seems that the icon adds some confusion, but it helps workflows where users use watches:
- even when they are not paused
- have some non-deterministic value, e.g. Math.random()

I think this is sufficient reason to keep it around, but please comment if you think otherwise.