While the research acknowledged that schools were working in clusters to ensure coherence, time required for this could detract from other activity.
Er i'r ymchwil gydnabod bod ysgolion yn gweithio mewn clystyrau i sicrhau cydlyniaeth, gallai'r amser a oedd ei angen i wneud hyn dynnu sylw oddi ar weithgarwch arall.