I read it all the time here on SF, people advising against using any cream etc. I may agree that I hyperbolized a bit.
Cordovan is extremely resilient and it's rare for it to have dried out. A light application of any conditioner would be sufficient if it had.
Using Obenauf's is beyond overkill, it's not going to do any favours for the Cordovan regardless of how soft/supple the shoes may now feel, but as I say it is resilient.
I fully agree on the overkill; I certainly won't use Obenauf's on my other shell cordovan pair (for now) the RL marlow, but I won't be as afraid of doing harm to them as I were before.
Cordovan is extremely resilient and often outlast calf leathers which gets destroyed by as much crap treatment as shell can go through. The reason I deceided to experiment on this was after seeing this thread; dry rot. I can only think what my pair has gone through whithout any treatment at all; daily use without shoe trees; dried by a heat source when soaked; stuffed full of wax; sitting in a box for years. To think that a pea sized amount of Renovateur is going to replace all oil lost during all these years, possbly decades, is naive IMO. Of course, I'm not at all an expert, but that's just my opinion.