“…It is an open question as to what extent the professional experience of teachers promotes and cultivates adaptive expertise with regard to adequate students' support in individualized lessons. For instance, Christophel (2014) demonstrated that more experienced teachers did not give more appropriate feedback (i.e., feedback that offers phase-specific information) but actually gave more inappropriate feedback than less experienced teachers (e.g., feedback that does not support the task completion but reduces the learner's amount of cognitive resources available for processing the relevant information; Sweller, 2005). Christophel (2014) studied 30 more experienced teachers with a mean professional experience of 11.15 years ( SD = 12.85) and 30 less experienced teachers with a mean professional experience of 42.07 days ( SD = 89.40).…”