Excellent post. The only addition I'd make is that the Ph.D. title seems to be slowly replacing the Th.D./D.Th. as the highest degree is Christian circles. The places that I'm familiar with in the US that retain the "Th.D." are mostly divinity schools at universities that have a religious studies department under arts and sciences that awards the Ph.D. Interestingly, at some schools like Duke the Th.D. is more ministerially focused than the Ph.D., while at others like Harvard the two doctorates are structurally identical.