Does anyone know if the model 9444A amp could function with a 4ohm load in bridge mode?

All the specs in the old documentation seem to indicate the min impedance of 8ohms in bridged mode.

I have a whole rack full of these things which have been running 4 ohm loads for at least the last 14 years (probably more like 20 years). So it seems to work but we have had reliability problems and lots of repairs. So apparently no one checked the specifications when the system design was put together 20 some years ago.

Thanks for any input...