its funny you should ask this question, I had to actually be taken off Testim because of the same question you are asking. I also had to switch diffrent times of the day. This was when I lived in O-town,FL.
My levels were good and bad but it was because of the lotions, soaps and just over all dry skin.
I would try to do cardio after applying 2 hrs exactly and it would build up in the shoulder areas, it looked like someone oiled up my shoulders. The rest of my arms were dry. But I felt as if I wasn't getting the effects like I was in the begining after 8 months of testim. So I went with shots. weekly. My urologist did bw weekly to confirm this. Even applied it himself in several tries. I had to see a dermatologist to see about getting special soap and all that stuff. It turned out it was just way tooo much money. My depo test costed 10.00 200ml pharmacia brand with my old good insurance. (now its 20.00) You know how much a 3 months supply costed of Testim 75.00 with my good insurance. Then you had to add up the dermatologist sold and not covered by insurance soaps and skin cleaner. We also had a new born towards the 9th month in the home. I just said to my Dr. that its just too much of an inconvience and cost. Plus I'm the stay at home dad so I was changing diapers frequently and worried about passing it on to my son.
I have heard people say they have been on the gels for years and no problems. So I think its individual, some absorb and feel great others prob lose most of it on contact from skin residue build ups (lotions,soaps)