I don't think mixing primer with foundation sheers out the foundation like it would if you mixed it with a moisturizer. I usually mix a silicone-based primer with MUFE HD and the result is the same as it is if I do primer first, then foundation (except it saves time haha)
Thanks, thats a good tip actually. I've been mixing my foundation with moisturizer and I'm not in love with the coverage but I love how it applys smoother.