In this paper, we present an optimized approach, based on a competitive breadth-first exploration of the analysis tree, for an interactive interpretation of off-line sketch. The competitive breadth-first exploration of the analysis tree, allows to compare several hypotheses of interpretation to deal with confusion. Unfortunately, in practice these methods are rarely used because they often induce a large combinatory. This paper presents an optimization strategy to minimize the combinatory. The aim is to demonstrate the relevance of a competitive breadth-first exploration in off-line document analysis, in particular when the approach is interactive, ie the user is involved into the loop analysis. This paper demonstrates this optimized interactive analysis method on off-line handwritten 2D architectural floor plans.