I'm not sure where you got your info from but there's a big difference in lsat vs. gpa depending on school, gpa is between 15-30% of index scores on average with most school around 20%, the rest is lsat. Although even with a great lsat I would imagine a very poor gpa would have to be explained in order to be accepted.
While some schools may weigh them equally, certainly not all schools do. Go to the LSAC site and you can print out the index formula for just about every school. With relatively simple math...