A system and method for merge-sequencing ordered subsets of items into a single merged set in a predetermined sorted sequence and error-checking the resulting merged set to provide information about out of order items to allow for efficient error correction methods. The system uses an outcome verifier module to ensure that items placed onto the single merged set are in the proper sequence. Items that are not in the proper sequence are temporarily removed from the merged set. If it is determined that items are missing from the sorted sequence a placeholder may be inserted to mark the place of missing items.