"Benefits Realisation" or "Impact Analysis"

Far too many projects have no follow-up at all.  The job is done and everyone moves on.  "Benefits Realisation" is an improvement - but there is a risk that in focusing on benefits the overall impact of the project is missed - and that lessons learned are missed.  Any project that is self-aware enough to have committed effort to "Benefits Realisation" should be self-aware enough to realise that "Impact Analysis" would be more useful and clear sighted.