Not sure. Technically, pullers pull more than pushers. To be honest, its probably “enough” to get by for those running basically stock on normal road conditions. The duct stuff for the ic didn’t come about till later and most don’t do a fan on the ic when they have the ducts. I think jbintx was the first to add a pusher to the ic with the ducts.
My theory (and just my own thinking) is to pull the air through the engine rad, direct it under the car via pusher on the ic, then push it out. So a pull on the main rad, then push on the ic rad should work great. I know the rad will heat the air before getting it to the ic rad, but I think of it as overall airflow and speed to get it in and out as easily as possible. Again, my own theory