This study investigated the effect of video-based teaching practice followed by focused group discussion via electronic collaborative discussion forum (ECDF) on the development of teacher competences. The trend of change on teacher competences of 30 Iranian English as foreign language teachers was traced before and after treatment on quantitative and qualitative measures. First, a newly designed and validated teacher assessment questionnaire named Teacher Balanced Score Card (TBSC) was used to quantitatively account for the developments of teacher competences including clinical, critical, technical and personal from teacher, student and administrative perspectives. In quantitative measure, supervisors' real classroom non-participant observations and theme elicitation through log analysis of ECDF according to a predetermined data coding schemata helped documenting evidences for teacher competence development on TBSC measure in pretest/posttest design. Multivariate analysis of variance results indicated that there were significant changes in technical and clinical competences. The theme elicitation in log analysis of ECDF implies that the required infrastructure for incorporation of technology, culture cultivation of its use, its role in establishing non-threatening supportive platform for teacher evaluation and its potential in teacher reflection, change initiation and management should be revisited at high levels of policy making and local levels.