Some customers review issues (red lights) in InFlight before IBM has a chance to send a manual review. The diagnosis information that comes from SI and is dumped into InFlight contains some useful info (such as issue on Output side of map, the map name, the ubiquitous mandatory data missing info and some eyecatchers that might help with block and field info.
If say an invoice contains many many line items the info in InFlight and often in the human response still does not identify the actual line in the original document that caused the issue. Customer still needs to do some detective work. It seems logical that SI knows where it was in the data when it hit the error. Is there currently further info that could be dumped from SI into InFlight that might help customers diagnose issues (eg today we dump lvl 4 info and with a switch we could dump lvl 5 info).