It's not accounting magic at all. A $1000 server with a 4 year life span is expensed at $250 a year. A $1000 server with a 6 year life span is expensed at $16

It's not accounting magic at all. A $1000 server with a 4 year life span is expensed at $250 a year. A $1000 server with a 6 year life span is expensed at $167 a year. You convert your server lifespan from the former to the latter you get $83, or 33%, savings a year. If you (intend to) keep your servers for 6 years and do not make this adjustment, then you're doing a false accounting, not the other way around.