CTO at Revana. Technical co-founder at Demandbase. Innovator, startup advisor and Lean Startup evangelist.
If you are using a Lean Startup approach, then the question becomes what is the fastest, most efficient and cost effective way to build, measure and validate your "value hypothesis". Does that require implementation, or can you validate quickly it using some of the excellent prototyping tools out there like: http://invisionapp.com