Nobody is seriously claiming that circumcision prevents getting AIDS. The claims are about a risk reduction, not more and not less.

In that recent study in SCIENCE I have referenced above 3274 South African men considering circumcision were split in two equally large groups, one was then circumcised, the other not. At a follow up after two years, 20 in the circumcised group tested positive for HIV, and 49 in the uncircumcised group. The self reported sex patterns were comparable.

Now, if you want to make this difference of 29 look big you report the relative risk reduction for it is 61 %. If you want to make this difference look small you report the absolute risk reduction which is close to but less than 1 %.

Wolfgang