where are the 3 tiles that are cracking at? i am having my granite put in in the next week and it is replacing ceramic tile in the same area. ater 18 years there was not a single crack in the ceramic so i am hopeful i will have the same luck with the granite.
at the recommendation of a friend who has done many coaches, i am putting a high end anti fracture membrane under the granite. it is called sam3 by NAC products.
http://www.nacproducts.com/Sam3.htm
i guess i will see how mine works out. i hope you figure yours out as well. i have never taken grout out, but i know there are tools to do it and from what i can tell it is just work and time as long as you are careful. i bought color matched silicone caulk made by the grout company to do around my exterior edges or wherever the granite touches a wall or cabinent.
tom