hehe, bear with me, I'm newish to this style of gaming and I'm sure it's been covered before, I just thought I'd share my experience of it. :)

I was playing a game on either Sunday or Monday night in the zone, before we played we had a chat and it seemed that we were fairly evenly matched (assuming that we were both telling the truth) in we went, carried on as normal, no monument, low resources, tech level 1 beginning.

He was on the left of the map I was on the right directly opposite him, I started as normal, workers etc, move to tech 2 (he beat me to it), produce a few trooper incase he plans on rushing. After I reached tech 3 I had most of the map scouted and there was a huge area near his base with free space - so I moved 3 troopers and 2 workers and set them to build a fortress and then a heavy weapons factory, meanwhile I start shipping some workers up and begin carbon and ore collecting and building a command center and a second airbase.

From the original base I move some Tie to the other side of his base, along with a few troopers and some mech

I sent them in and a few seconds later sent in my pummels and artillery from my new base to attack him from the other side, in the hope of catching him off guard ;) true enough he didn't heed the second warning of being attacked and sent everything to take out the decoy attack at the other side, I was able to get in and destroy the command center, some processing plants and some house and AA defence before he was able to regroup and destroy my pummels (from the Fortress containing a heap of workers and his fighters).

He took the lull in play to sent his troops down to my original base and sent his workers back to work, meanwhile I've been pouring out mounted troopers and pummels again - I send them in, and send a token defence to my old base which he's welcome too. And as I am flattening his base one of his fighters flies over my new one and all he can say "Uh Oh" and 5 minutes later he resigns lol :D

Forward bases are great me thinks - unless it happens to be you on the wrong side of one ;)

That why you guys need to build sentries outpost. This prevents this stragey from happening. If someone destroys a sentries outpost then you will be encouraged to investigate it and you may discover a base being build then you come in and blast it off the face of the Planet that you are on :D . Also another good one to prevent this is Patroling with troops or Fighters. Fighters are the best patrols. You will be aware of everything happening outside of your base with your patrols. thought i tell yall a good counter measure against this stragey.