I think it's worth emphasizing that the exclusion of "open" accounts from utilization applies to the newer versions of FICO. In my case, I have two NPSL accounts (both Chase CCs). On both EQ (a newer version of FICO, Beacon 5.0) and TU (the older TU98 version), these accounts are reported as "open". The past high balances are also reported on both reports. My EQ utilization is 1%, which clearly excludes the current balances and the prior high balances in the calculation. However, my TU utilization is calculated at 4%, which does include the current and past high balances.
So, with holiday shopping season rapidly approaching, I'll be using my Chase cards. My TU score might take a beating, but the EQ score will continue to blissfully ignore the expected increase in credit card use.