Sect War 2
Draco and Eva had time to breakthrough into Qi Condensation for all three of their methods, and boy did it make a difference. It turns out that body cultivation was slow for them because of how thick their bloodline was and how special their rebuilt bodies were.
In other words, their base human bodies were better than everyone else in this world, so it took more effort to mold them according to the various techniques. That was why it took them so many weeks to go from Muscle Tempering to the peak of Flesh Hardening.
Of course, that was without using any pills or the like, specifically taking into account their Dragon Ascension Chant and Phoenix Rebirth mantra. However, after entering Qi Condensation, whether it was the aforementioned cultivation techniques or the other two, it was like smooth like a water slide.