Thanks! And yes, since every grass block has it's own block model, it does cause some lag, but nothing terrible. I guess the only way to say for sure if it will lag for you is if you go and test it out.
Nope I didnt delete anything. Im using MultiMc with Optifine. Maybe you gotta find a way to make it compatible? Not sure. I was also on 1.8 if thats helps.
Hmm.. I'm not sure what could be going wrong. Could you open it up with vanilla minecraft and tell me if you have the same problem? Because then I would have some idea of weather it was the mod or just a problem with the pack that was causing your issue.