There's no TRICK.... It's pure math.It doesn't matter what numbers you use, what "sequence" you use. Make up your own numbers and do the math. Start off both Nat Gas Price of $2.00 and ETF $2.00 for easy comparision.
Now do your Nat Gas price changes and then go back to $2.00. Now, calculate your ETF share price.
What you will see, no matter how the Nat Gas price changes, when it goes back to $2.00 the ETF will be less than $2.00.
PURE MATH..... don't trust me, do it yourself, make up your own gas price changes and then go back to $2.00 and then do the math on the ETF.