im not convinced about it being the case with frillys,but havnt bred them my self,ive never heard of an all male,or all female clutch,its also not in most reptiles,what u mention in frillys was supposedly beleived to possably occur in bearded dragons to,but mine ive bred have ended up a mix of both sexes,water dragons is a different story,the temp definatly determines there sex,ive incubated water dragons in the same incubater as the beardeds and they all turned out male,thats 11 clutches varying from 9 to 16 eggs per clutch,all were male,this season i raised the temps a touch to try for all females,early days still,but the 12 i have all appear female,no red in chests yet,which usually show through by this time,so fingers crossed i got the temps sussed,lol,with juvie dragons,especially beardeds and frillys its the luck of the draw im afraid,if u get 3 or more u stand a great chance of at least getting a pr