[Musashi3000GT]

I guess I am an idiot when it comes to tires, I know everything to know about tire maintenence and care but I still ignored it. Well I bought some Falken G/Ts a year ago and last week my car started feeling bouncy. it hopped at about 60mph. I took it to get balanced and the balance was way off.......thats not the only problem. both of my rear tires have these dips in them. the tread is perfect, not worn or anything but if you place your hand in the center of the tread and roll the tire so your palm feels the surface of the tire, well then you palm starts going up and down slightly. the surface dips and them comes back up, it dips about four times and is making my tail hop. Wierd, the kid at the tire shop said its cause my shocks went bad. I say bull, my shocks are spanking new. I got KYB G2 Nitro gas shocks, no way they would go bad after only 12000 miles. no it has to be something else, I never rotated them cause I was lazy, I did run them a little under inflated and my allignment might not be perfect but seriously......those bumps are not natural nor are they products of the maintenence I've ignored. Any clues as to what it might be?