Brian, I used finasteride to treat urinary symptoms from BPH. I had about a 35% decrease in PSA and no improvement in urinary symtoms. I stopped finasteride after several years and experienced a three fold increase in PSA about a year later.
Here are a couple of links from the PCRI web site that may answer some of your technical questions.
The first article was written by David G. Bostwick M.D., M.B.A., Bostwick Laboratories and the other by Dr. Scholz.
Dx Feb. 2008, at age 71, PSA 9.1, G8, T1c
Eligard 3 mo. shot, Feb. 2008
daVinci surgery May 2008, G8(5+3), pT2c,N0,MX,R0
BCR 2 1/2 yrs after surgery
Salvage Radiation (IMRT), Dec. 2010 - Feb. 2011
PSA 0.10 seven months after IMRT, PSADT 8.6 months