Escape to the Movies: Transformers 2

I'm really rather proud of this one, though I wish there were more synonyms for the word "douchebag"...


http://www.escapistmagazine.com/videos/view/escape-to-the-movies/797-Transformers-Revenge

One thing I'd like to get into here that I DIDN'T get to "bring up" in the review for purposes of time. (SPOILER WARNING, I guess) The "2nd act obstacle" for Shia Labeouf is being stalked around college by a "hawt" sexually-aggressive classmate who turns out to be a Decepticon who can transform into a human chick. Yeah.

Two questions about that:

1.) Isn't the whole point of the "robots in disguise" thing that these things are mechanical beings and have to "dress up" as whatever car, appliances or vehicle best matches their relative dimensions? In other words, if they can hide as people... why don't they ALL just do that!? Wouldn't that make slipping unknown amongst the natives a million times easier?

2.) Megatron, as evidenced by this film, really SUCKS at resource-management. He has a soldier who can look exactly like a human, who could be sneaking into military installations or ANYWHERE else, but instead it's job is to collect The Kid? Something that it's already been demonstrated that ANY of the grunts can easily do? Later on, in the middle of a big firefight, he summons up Devastator, a behemoth made of seven(?) combined construction-vehicles who stands about 300 to 350 feet tall. HIS job? Dig a hole.