Regarding DHT mentioned in wd40's link, the article discusses the role of DHT within the prostate cells. Although it may be "2.5 times more potent as a male sex hormone than testosterone", this may be in relation to its function within the prostate only. I'm not sure that one can conclude from this that DHT controls sex drive. I interpret it as a byproduct of testosterone used internal to prostate cells.
To add to the poll, I have personally not seen any difference in sex drive after surgery. my general "horny" cycles seem to be exactly the same as prior to surgery.
Age:45 (44 when diagnosed)
Father diagnosed and cured at age 52.
08/21/07: Diagnosed with T1c cancer
1 of 12 biopsy cores positive; 10% tissue
Gleason score: 3+3=6
PSA level prior to biopsy: 4.3 (velocity < 0.4ng/ml)
10/19/07: da Vinci prostatectomy by Dr. Vipul Patel
Difficult surgery due to prostate inflammation.
Both nerve bundles spared.
Spongy erections began within 24hrs of surgery!
10/24/07: Catheter out; down to 1 Serenity pad/day next day.
Final pathology: neg margins, no capsular penetration,
Gleason 3+3=6, 5% tumor involvement, multi-focal.
11/04/07 First usable erection with Cialis
11/22/07 Thanksgiving - Bye-bye, pads
01/17/08 First post-surgery PSA result: < 0.008 ng/ml