Originally Posted by
rpenmanparker
Just seems right. I never saw it mentioned anywhere. Just came up with it, apparently like many others. That alone attests to its reasonableness. Where you have to be sensible is in progressive improvements. Say you spend $200 to save 200 grams. And suppose a year later you decide to spend $400 more to save another 200 grams on the same part. It lookss like $2/g on the second purchase, but it could have been $1/g if that had been the first purchase. Funny.
Ah, yes,
One has to account for currency inflation; tire inflation; rising sales tax; rising carpet tacks; trade duties; and tirade doodies.... (That last one is for when ya pinch a loaf to lose half a pound)