Heaspace title function: too long titles?

Hi guys
I am using the great Headspace2 on all my sites, http://www.spacessential.com and http://www.fengshuibc.com
Since the beginning I have used the page title function of the plugin with %%title%% :: and thought that it was replacing the title of the page with another one put in this box. The idea was to have some user friendly page titles and then convert them into something more SEO refined for google.
However by looking at some pages from my sites I found with google I’ve realized that actually headspace since to ADD the title after %%title%% :: to my page title: creating very long and redundant page titles that are of course not good for google.
Is that the case? If so what is the point of using %%title%% ::? If I use a title in this box without %%title%% :: will it replace the title page?
Thanks for your help guys.