Too low of a dose to see AI properties?

Here is the situtaion. I am currently conducting some research using ARR letrozole. Along with 320mg/wk of test e, I have been giving my test subjects .5mg of letro EOD for a total of 2mg/wk. I have noticed the subjects have had a great reduction in libido as well as having dry eyes. I was thinking about reducing the dosage of letro to 3x a week at .25mg on Mon .5mg on Thurs and .25mg on Sun for a total of 1mg/wk. Another varible to consider is that the test subjects have also been getting 10mg of nolva ED and will continue to do so along with the new dosing.

---> Here is the question. Do you think this dosage is going to be to low to see any type of AI properties?

I was thinking about switching to liquidex, however I have had great sucess in my experiments with letro in the past, and I come from the thought if it is not broken why fix it. The problem is I have not seen these sides at the .5mg EOD in subjects in previous experiments. So i'm not exactly sure whats going on here.