Greta is not so much dainty, as she is fragile. She does have small feet, but she is considered "oversized", because she is tall and lankier. I think this slender physique may have contributed to her joint problems. Unlike Gracey, Lady and Betti, Greta has NEVER been able to assume the frog position. All of her life she has been stiff and her joints snap and grind. Poor old girl. We are always afraid she will hurt herself when she plays. Most of her life she's had a limp. Once her hip healed from the surgery to implant a pin to stabilize it, she tore the cruciate ligament in her opposite hind knee. We opted to not have the surgery performed for that, because of the hardship of going through ANOTHER treatment involving anesthesia, which would increase her chances of dying from heart failure.
Betti, on the other hand, is shorter and muscular. She hops around like a little flea and sprawls out like a basking frog.
I think it is better for the rottweilers, as a breed, to be shorter and stockier, more muscular, etc. and with proper weight to prevent the bone/growth issues. That is why it is silly when people attempt to breed them to be so huge deliberately. But, then again, we humans with our eugenics are always asking for trouble in the "genetic engineering" department.