Sweet vs Unsweet Tea

So, I tried to put one over on DH last night. We have been drinking sweet tea for the past year, but I am worried about the calories. I decided I wanted to switch to tea sweetened with splenda. Mark is very sensitive to the artificial sweeteners and I knew I had my work cut out for me. I made the batch with half sugar and have splenda. It seemed like a good way to ease into it. We had a lovely dinner: veal parm, spaghetti, good wine, and Mark and I had tea. Afterwards, Mark said, "thanks for making the tea, I meant to do it." I smiled and replied, "no problem!" relieved because I started getting a little worried when he brought up the tea. Then he hesitantly asks, "um.....so how did you make it?" My mom knew my little secret and started laughing, but I just looked at my husband and told him, "I hate you." Then I confessed. Drat.