Totally agree. The material is hacky stuff but the delivery is what really makes it amateurish. If you give this trash writing to a good comic like Louie or Dave they could actually make it work, inspite of the hacky material. That's because they're real professionals who developed their delivery, timing, tone etc. over years of performing. They learned the intangibles and probably had a natural gift for performing and speaking from which to build on.
Schaub clearly just doesn't have the natural gifts to build upon and he's not smart enough to recognize and hone the nuances that make a comedian good. He's almost 10 years into the game and still sounds like a first-year open mic guy. He's clearly not cut out for this business and his relationship with Joe is the only reason why he's been able to uphold this comedian facade for so long.