Hi I was hoping you guys can advise me, your advice before has always been spot on. Anyway I've decided to change my rear 8speed cassette 11/27 to a 12/26 do I need to shorten or lengthen my chain. Many thanks guys.
That's the wrong way of looking at it. A link is the smallest unit that can be removed so that the chain can still form a continuous loop. A link is a two-part affair.
By your reasoning one cannot remove a link from a chain and re-assemble the chain. In that world we will only have half-link chains.