I've seen this, and it's horrific. It was 2008, and I worked for a large investment bank (think in the Goldman Sachs echelon). I was on a transition team movin

I've seen this, and it's horrific. It was 2008, and I worked for a large investment bank (think in the Goldman Sachs echelon). I was on a transition team moving risk analysis for $1bn in synthetic CDO assets from Excel spreadsheets to a formal system. There was zero documentation. Formulas were not internally consistent. Their version of version control was saving a new copy of the spreadsheet every day. Their version of day-to-day analysis was copying tabs with a specific naming scheme so that the macros would pick up yesterday's data properly. Have you ever seen a spreadsheet generate XML? Shell out to a command line program? Import the XML that command line program generated? Generate a CSV file? And then FTP that CSV file to a central reporting system? I have, and it haunts me to this day.