David, I'm still learning, so I don't know if this make sense.
Just crossed my mind, there is one good example in Tutorial: Database Find which is repetitive, but returning only one row because of uinque id. It is obvious there can't be a problem by modeler (he knows only one row can be returned) so it doesn't make sense to have warnings (just my opinion). In that case, modeler should be able to insert another exit type (non-repetitive). Or maybe even better, to have trigger which converts repetitive to non-repetitive flow.
I realized later, there is a Collections->First which is doing exactly what I want: converting repetitive exit to non-repetitive flow afterwards.
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