Of the 24 possibilities of base pairs in a single base pair bulge, the G-G combination results in a -0.4J free energy, the lowest of the choices, acting with a significant attractive force without actually bonding.
So, if any single-bp-bulge is present, automatically converting it into a G-G BP should result in a +2 scoring for each bulge.
Not sure I follow - what is a single basepair bulge?
I was wondering the samething Hog. Perhaps a 1-1 loop?
Ah, right, sorry. a 1-1.
But a picture says more than words: See
http://images.gizmag.com/inline/etern…
pairs 26-37, 58-74, and 61-71.
If they get transformed into G-Gs, the entire haipin becomes extremely stable.
Was that a clear explanation of your questions?
Yes, having two Gs is a stable way to boost 1-1 loops 
Yes . A g-g mismatch in a 1-1 loop is the best boost to use in most cases. Fairly common knowledge. Salish, have you read any guides on puzzle solving or boosting? This may help see all the different ways to boost and what energy benefits you get with various mismatches in all types of loops.
Jnicol even has charted out all of the possibilities In his energy chart. Sorry but I can’t get to his link right now but you can find him in players list and he has link on his profile page.