Gi doesn't make your no gi better, nor does football make your rugby better. It's two different sports.
Anyone that says to a grappler that you need the gi to get better at no-gi, I find obnoxious. And, on that note, anyone that says that the gi sucks is retarded. It is also a beautiful sport.
But, also the notion that you need to, you must train both is equally fascist.
I don't know the answer to this, but do you see people screaming at 100 meter hurdle runners that they need to *equally* train 800 to make their 100 better, or vice versa? Anyways, they too are different sports.