25R-diol is going to create a lot of testosterone and with the 3,4-DVTHF freeing it up, the odds of estrogen conversion increase. That can cause shutdown and estro related sides, so the AI is just insurance, not everyone needs it probably but it's a good idea to include and help elevate test even higher anyway (or at least negate any shutdown).
NOW GO GET SOME MASSFX!!!!
NOW GO GET SOME MASSFX!!!!