Trying to use the 'merge' tool within ModelBuilder in conjunction with an iterator is a headache. Say I have a model that iterates through an entire database, selects feature classes that share similar file names to pair/merge together, and then moves on to the next pair. The two+ feature classes in each individual merge share a schema. But, at the next iteration, if the next pair doesn't have the same schema as the first go-round, the tool either fails or creates countless <Null> values.
PLEASE find a way to add the functionality to "field_mappings.removeAll()" after each iteration, similar to how a user would manually select the 'reset' button after running the merge tool once. Maybe a check box or something? Just like you have for including source values or not.
