Most likely. But ever wondered when an attack comes people just don't know what to do? You could better tell them how to block certain attacks and you probably know the rest.
The blocking-system in RA3 seems pretty obvious to me. In many cases it seems to be proper scouting: Many players often do not scout properly and don't use the facts that can be observed when doing so. There's also much logic involved.
For example when you see guardian tanks and manage to send a scout to the enemy base and find his warfactory on lvl1 (little blue lights on top of the building) you may extract quite a lot of information from that:
1. His MCV is no longer in the mainbase, because no allies-player is gonna afford a second warfac at an expansion.
2. If your scout took one of the few available routes in and out of the base and didn't spot the MCV on its way, you can predict with high accuracy where the MCV was moving to and where you will find the next expansion.
3. The opponent won't not able to build any more Guardians until the MCV returns.
4. Unlikely/Less likely possibilites:
-MCV-Sell (currently no strategies are known that work this way)
-MCV was teleported to a new location with the chronoswap-ability (there are quite some players out there that actually choose that ability)
-MCV was packed up to move closer to water for building a harbour (no allied player ever needs a harbour so bad, that he would move the MCV just for that)
(Remember: I just observed 2 little details and was able to gain insight to the enemy's strategy. That are much more usable facts from little details than in any other strategy-game I know of.)
Example why scouting is important, the match between freezy and me:
I sold these airfields and I don't know if he saw that, but he kept building masses of IFVs, instead of teching up for Mirages to squeeze me. Something else I noticed was, that he didn't scout for my expansion points properly, and he had more than one chance to kill my stuff up there without losing much time and troops. He also missed to build up the expansion right next to his base. When I attacked his MCV with my vindicators, I saw where his MCV was moving to and I immediately knew where two of his expansions will be found at as soon as my taskforce was ready. Quite some time later my first wave of groundunits then attacked one of these locations which were totally unprepared. I found a MCV, one Airfield and a Refinery, all of them unarmed and ready for destruction. In panic he quickly tried to pull up a barracks and a tower and seemed surprised that I'm able to afford such an effective army, just because he stopped sending scouts to my base in lategame...