Greatwood Support does not make sense to use

The idea behind this support gem seems to be combining your multiple totems into a single totem that does more damage. The math seems to be way off however. +1 totem limit is effectively 100% more totem damage. Giving up totem limit and a support slot for 10%-40% more damage makes no sense.

If I take 2 or 3 totems and combine them into 1 super totem, that super totem should do (at minimum) as much damage as 2-3 totems combined.