You're asking for trouble doing this, you'd end up with severe overcrowding and a performance issue with the guard having to use the crowded train procedure at a lot of stations.2-car 195 on the Manchester which has a more frequent service).
You also have the ongoing TRU works which means that often the Calder Valley service is the only one running between Manchester and Leeds.
To me, Northern needs to do more with yield management on the Calder Valley, they still routinely have very cheap AP/APOD available on services which they know are going to be short formed.