First, let me say that I'm not the type of person that, when criticizing someone at their work, does so in an automatic "I could do it better" methodology. Grisham's a better commentator than I'd be. Kozlov's a better wrestler than I would be. That doesn't mean they're good. That just means I'd suck even more. But just because you suck at something doesn't mean you can't point out when someone else sucks. I'm no personal chef but I can tell when someone didn't cook my steak all the way.
TELLING THE STORY
A good play-by-play commentator tells the story of the match without getting sidetracked too often and is able to bring a new perspective to things. Remember when Jim Ross would talk about a feud that was going on and say how despicable he thought the heel was or how good the face was? Grisham is more of a "here are the facts, and that's it" type of guy. He's the equivalent of a narrator that doesn't have any character but literally is just listing what has happened. Ever been to a meeting where someone reads the minutes of the last meeting? That's what Grisham does. No new spin on things. No insight into his viewpoint on the situation. If Dolph Ziggler is in a love triangle with Vickie Guerrero and Kaitlyn, Grisham will tell you "this is a love triangle" and nothing more. Now, Striker will do the opposite, giving his personal opinion about the most mundane things, adding 100 nicknames to everything, and trying desperately to throw whatever random reference he thought of on the toilet earlier that day into it, no matter how big the stretch. Striker will comment on the boot laces a wrestler wears and tell you the size, color, where they were made, who made them, a story about how they were made and why the wrestler chose them, and then somehow tie it all into an episode of Charles in Charge. Grisham will tell you "those are boot laces". He might throw you a bone and say "they're used to keep the boots from falling off your foot".
A good play-by-play commentator knows his stuff. If someone hits a Ura-nage, they don't mistakenly call it a chokeslam. A hurricanrana isn't a dropkick. Grisham seems to either not know the majority of the moves or just refuses to say their names. He's much more likely to say "that move" or try to cover it by calling everything a "modified" version of the most fundamental root of the move. Far be it from him to say "tornado DDT" rather than "a modified DDT" or "Christian....fighting back."
A good play-by-play commentator takes the previous two things and bundles them up with the proper emotion to sweep it all along. How much better was it when you would hear Jim Ross yell "Good God! They killed him!! As God as my witness he is broken in half!!!" Meanwhile, everything Grisham says comes out in the same nasaly monotone inflection. Remember when Christian made his return and all Todd had to say was "It's Christian" in a real blunt, "meh" kind of way? Ross would have gone nuts! He would have made it seem like the second coming of Jesus Christ - or at least, he'd have made it seem like something remotely important. What's pitiful is when Grisham does in fact try to sound excited. He comes off sounding like he's trying to sound excited, rather than actually being excited...kind of like how people sound when they're talking to toddlers and saying things like "Wow, trees ARE tall! You're right sweetheart!"
Right now, we've got a couple great things going on with the commentary in the WWE. Michael Cole's heel character is very entertaining in my mind, Striker (albeit annoying at times) tries to breathe a bit of fresh air into his performances and I can still see him being a staple of the desk much like Jerry Lawler has become. We also have Josh Mathews who in my opinion is EXTREMELY underrated on commentary. If I had things my way, I'd say they need to upgrade Mathews to fill in Grisham's Smackdown spot, throw Grisham into the backstage interviewer role (where it's much more acceptable to have zero personality and basically just act deadpan and monotone all the time), and they'd be much better off. And to his credit, Grisham IS good at the backstage interviewer role. I have no problem with him doing that. He accomplishes the job, looks intimidated, and doesn't steal the spotlight. He's perfect for that...just not commentary. To me, Mathews reminds me of Michael Cole whereas Todd Grisham conveniently reminds me of Todd Pettengill. Who is Todd Pettengill, you're saying? Exactly.