No Nightowl, there definately not hard to breed, infact if there healthy and happy in good condition, they'll bred readily. In the wild there is a great mortality rate among hatchlings due nature, predation etc, not many young make it from each clutch.
Females can retain sperm and clutch multiple times aswell, even separated from male after first mating she may cluch a few times, she can be holding/developing 3 clutches at the same time in diff stages of developement.
This balances out the high natural mortality rate, and feeds birds too!

Whats happening with mine this year i think is several factors.
while she mated (unexpectedly, yes were all learning lol) last year and was separated from the male right off, she produced 5 clutches with about 95% hatch rate, some 50 something eggs.
However this was not a good thing as she was barely still in her first year, but fortunately she was in good condition, it took heaps out of her though, and a while to re-condition her.
The male wasnt cooled because I was stupidly not expectying mating so young, but she still produced, as she would in the wild.
This year they wernt cooled, but mated, I think the eggs were all unfertilised, being fully mature now cooling as he would in the wild, may be more important. Cooling increases sperm count and fertility in the male apparently.
I think she is carrying eggs now and it will be intresting. Well have to see how it goes.