My wife and I have joint accounts for EVERYTHING. Thus, for the last 10+ years, our financial information should be showing as absolutely identical. We both subscribe to ScoreWatch and have alerts setup for all the available alert criteria. However, when OUR credit card balance changes, many times she gets an alert and her score is adjusted but mine is not.
I used to work for FICO in the fraud area (i.e. Falcon). We used to put a lot of effort into analyzing the performance of the scoring engine. However, it seems that the FICO scoring engine is completely arbitrary. For Falcon, there were very specific rules; e.g. if a tran is > 50 miles from the billing zip, if there is a $1 charge at a gas station and then a large purchase or several at an electronics or jewelry store, etc.
The folks on the FICO scoring side seem very reluctant to share the rules that they use in determining your score. Sure, there is very general advice about maintaining financial health and strength. But never anything prescriptive or specific.
