How Has Breeding Worked?

Although not a perfect guide to PoGo, previous Pokemon games have certainly provided some insight into how upcoming PoGo features will be implemented. Now that gender info has arrived, I would like to improve my keep/discard decisions in anticipation of breeding, even if past methods aren't a guarantee of how things will work in PoGo. I've only heard scattered bits of info about this so far, and I'd love to hear more.

So, I'm curious: in prior games, how has breeding worked? Have traits been heritable in all-or-nothing ways, such that a 0/10/15 and a 10/15/15 could produce only a 0/10/15, 0/15/15, 10/10/15, or 10/15/15?

Or are traits heritable in gradations, so that an 8/11/15 could be produced from that original pairing - effectively using the limited dice roll mechanic from egg hatching, but using parent values to limit the domain of possibilities?

Could the same pair breed any number of times? If someone has a M/F pair of 100% Dragonites, might they be able to pump out 100% Dragonites (or Dratinis) one after another? (And if Dratinis, how will Eeveelutions work? Would two Jolteons produce a Jolteon, or an Eevee?)

Lastly, I'm also curious about how Ditto has worked in the past, although I'd be a little sad to learn that a 100% Ditto might be especially useful... a 504CP Rattata ran from me yesterday so there's a chance I just missed out on one.