I don't believe that unless you can show me proof. Statistics of at least 100 breeds with epic parents vs. juveniles with a significant difference in the output of rares vs commons. Of course you have to have the same parents, once in juvenile, once in epic. If you wanna breed 200x the same colors and write down what you get every time, go ahead. I have better things to do with my game time...
According to my experience, and probably also the game code, which some people here can read and maybe confirm me, it is not the case that you get "better" outcomes (not always a rare is better) when using epics, I have bred ultra rares using juveniles, and I get tons and tons of commons when I breed for primes using lvl 15 dragons. But belief can move mountains, as one says. Maybe it does not work for me because I don't believe it...
i think i may have a grand total of 20 epic dragons. seriously. 98% of mine are at level 4. i breed the level 4s. i get rare, super, ultra. i got a diamond off of 2 level 4s.
Believe @JulieWild because she has been playing a long time. I haven't kept track either but with 1,303 dragons, 1,050 unique dragons, I haven't noticed any pattern to when I get Ultras, SR, R or Commons. You would think two UR dragons whether they are level 4 or 15 would give you UR but I've gotten Fire dragons from those pairs which is as common as you can get. Although there are rules to the way dragons breed, you have to be a braniac to understand them because then they throw special breeding rules in on certain dragons too. So I just breed the dragons I want and hope for the best.
I have been playing DS since Jan. 1, 2013.
Also, other dragon breeding games also instruct you to breed older dragons. Try playing DragonVale, which uses about the same rules as DS, but has as a breeding guide to use dragons over level 11 for better outcomes.
What do you think?