As banks have realized the need to look on their business in a process-oriented way, they have been engaged in numerous business process optimization or even reengineering (BPR) projects in the last decade to make their organizations more efficient. However, the success of BPR projects in banks varies significantly and it remains a challenge to systematically discover weaknesses in business process landscapes. In particular, automatic semantic analysis of business processes for different types of weaknesses (i.e. media breaks, redundant consistency checks, or missing or inconsistent information) is yet in its infancy. Value from business process modeling can, however, only be unveiled when time-consuming, mostly manual business process analysis is performed and results in business process optimization. In this paper we develop a methodology for semi-automatic analysis and detection of weaknesses in semantically analyzable business process models. We argue that this contributes to systematically identify possible weaknesses in process models more efficiently and more effectively than manual analysis.