meh, it's a great route. Problem is there's very few intelligent players (this sounds rude, I really don't want it to be but I don't know how to phrase it better) that can use CG's properly without spending half their funds on CG's (specifically at the round start). It's an amazing wave tool as well.
The problem some people have with the route:
1) People slow their teching down beause they buy too many CG's. A good CG player can literally win the round on ~day 7 by himself. An early land stealing unit that can, if not massed, allows you to continue teching with 0 impairment and hit a massive power curve at CW's.
2) Losing flak is losing flak. Just because you can steal land with CGs doesn't mean you should.
3) It pisses off your alliance members that you either have so much land (and don't necessarily deserve it, silly logic often) or that you have spent so much money on CGs. This can, however, be a good thing if you can hold the land and hit a good power curve, but it also makes you a target with minimal defense and tons of land. Again, pisses of your alliance.
4) People like PA's too much
5) People like CW's too little (and would rather go nano/PA).
If I didn't make it clear, CG's should be nerfed or removed from the game. **** you Twigley I know you made the suggestion (as have other people) like 133 years ago.