I went through this when I tried to use a drip shield (now I hate them). What I discovered is the accumulation of oil inside the outer atty wall and inner drip shield wall give the FALSE "gurgle" sound that there is still oil in the atty. This made it seem like the atty had oil when it was actually dry! Of course it then tasted like crap. I got tired of trying to remember how much oil was in there and tossed the shield. My solution was going back to my old Prodigy V2 which has the best reservior ever and prevents run off and an oily mess.