I've just barely begun to get into this IV breeding game. I don't think I've ever gotten a perfect that would match those 2. But I've been close. It's all very random though. I'd get some that have great potential, minus 2 or 3 stats, but the rest of the eggs in the batch were not that great. Would I then have to breed that near perfect with a Ditto that would cover the gaps? Then I assume it would lead to more breeding where everything is passed down to complete the most IV coverage?
Yeah, its just a question of having the stats you want perfect IVs in across both parents - the more overlap there is, the more likely it is the kid will inherit 'overlap' stats.
So a typical breed chain would be
A: XXxxXX (4 IV ditto with destiny knot)
B: xxxxxx (worst case scenario pokeyman with nothing - if its the nature you want give it an everstone)
C: Ditto with xxXXXX or XXXXxx as next parent in waiting
As soon as you have a kid with XXxxxx or xxxxXX, swap him in with C, and each time you get a kid with more perfect IVs than whievers with the Ditto, switch them in as the species parent instead
Always use a pokemon with flame body (magmars and fletchinders are both easy finds) as your compulsory pokemon with eggs for faster hatching too