Not true, latex can go on oil if its prepped right, cleaned well and no
gloss. Cleaning well is not understood by many, oils from hands imbed
over the years in specific areas on doors, frames and windows which are
constantly touched, you realy need alcohol and care to clean these areas
well. Places that can`t realy ever be cleaned right are kitchens. I
don`t like latex on trim anyway, but failures are from poor prep. The
cost of proper prep for latex can make it more expensive then just using
oil primer from the start. Jobs ive seen fail were not prepped, the prep
can cost the same as the paint job, its an area often cheated on.