Limitation for tax penalties: emphasis on initiation of action preserves enforcement; reasonable cause evaluated by business realities.
Applicability of the limitation period is determined by the initiation of action rather than the formal start of penalty proceedings, making the triggering of enforcement activity the operative moment for limitation. The reasonable cause doctrine is applied with attention to the appellant's bank like operations despite its cooperative structure, recognizing long standing practices and business realities as bearing on culpability for transaction handling contraventions.