[Leherenn]

We used to do it at my previous company, maybe 30-40 engineers, but only 10%. It didn't really work, in the sense that no project went anywhere. Based on the feedback here, it seems to work if you can contribute to external projects, where it's easier to add marginal value.

In our case, everyone worked on the same project, so it was either develop some new features for the existing project, or create something brand new. We would develop some POC, and every time the answer by management was "that's cool, but we don't have the resources to polish it up/bring it to market and it's low priority". It was pretty depressing to me.