ITA with Holice .... cutting it down the centre would give you less fabric to work with at a time, though would waste more fabric. I did mine for both the 4PP and OBW as the full width. It's really not that hard to handle, so I'd suggest leaving it all in one.
I haven't looked at the video .... Holice mentioned the blocks are 11". I'm thinking that they must then be cut with an X to make four sets of triangles to piece for each posey. I did mine all in squares and cut my squares at 2-1/2", so each of my poseys finish at only 4". You can choose your size according to your fabric print size.
4PP is a fun project ... and oh so addictive ... Good Luck!