It's not just GM, all the manufacturers do this.

I do agree, if these engineers are not wrenching on their creations, they lack the understanding for our issues. Such as a job that could be easier by less then a 1/4 of clearance.

But with that being said, these v6 W platform cars are pretty easy to work on. Go to the LS4 powered W platform cars, that engine is shoehorned in.

Also, keep in mind, as our needs with cars increase (ABS, AirBags, improved suspensions, improved safety/crush zones for accidents, more entertainment electronics), all of these take there toll on space and weight.

When you get into a more performance oriented ride, like a v8 powered Camaro/Mustang/Charger/ect, part of that performance is making the most out of the space (need a big shoehorn to get some of those drive trains in).