Where are you getting your numbers?
Studies - not word of mouth - not that exotic vet who lives 80 miles, er 4 miles, er two blocks from you - state otherwise. Snakes optimize their caloric intake to coincide with energy expenditure. When they cut down their activity levels, some stop eating for extended periods of time.
Studies - not your invisible pink rabbit exotic vet - show that much more active snakes, including pregnant active female snakes with much quicker metabolisms, never approach 15% prey size. So c'mon, what orifice did you pull those numbers out of?
As Eric stated, that's why people often notice minimal (if any) weight loss when their snake goes on an extended fast.
Now if I may ask a small favor of you:
Please stop making inferences to my posts. Either you read things too fast, or your ability to comprehend things is compromised. I enjoy having discussions about things, I enjoy healthy debates and contemplating points of view in which people put actual thought.
I do not enjoy being misquoted or dealing with emotional people who constantly see their own insecurities reflected back in other people's posts. If you'd stop posting and listen to other people (not me, please block me) you might actually start filling your head with some useful info that will allow both you and your snake greater fulfillment.