Originally Posted by operator

That extra link on a system that is setup to max capcity of the rear derailleur means that it will be slack in the small/small combo. I've seen this before.

I guess you can tailor it to the application, but why bother calculating whether its at capacity or not. Big/Big eliminates any and all confusion.

Also, going back to the above. Setting the chain length with the derailleur pependicular method allows you to set a too short chain length if the derailleur does not have enough capacity. Big/Big + 2 eliminates this problem. It is always reliable, regardless.