Laser Eyes

Is it different when a girl checks a guy out versus when a guy does the stare?  Cause I mean, apparently all the girls I know can pinpoint whenever a girl is blocking my vision, but for the life of me, I can hardly tell whenever they are scoping guys out.  And I know they are cause they tell me afterwards!  The conversation goes something like this:

G: "So anyways, like, I didn't want to drink last night, but I had so much fun without alcohol--I only had two beers,two beers! but the boys were great.  I like meeting new people.  There was this one guy.. "

Me: "Mmm. yeah, you had fun?"

G: "You just checked out that girl didn't you?"

Me: "What? Me?"

G: "Yea you!"

Me: "No!  No.. um, so you had fun?"

G: "You totally were checking her out.  I have that skirt. That white one that everyone has.  Her ass was too big."

Me: "I was not!  Can't believe you would think so!  Anyways.. where were we?"

G: "Dude, it's so obvious.  Your head totally turned and you zoned out for a couple of seconds."

Me: "Uh.. ok."

G: "Anyways, I had so much fun with the boys last night! This one guy who was visiting from California was a blast."

Me: "What did you do?"

G: "Nothing much. We just played pool. Went to O'Morleys. The usual.. but they rocked hard! They were out til' 5 am!  I was gone by 4 am. But, it's so funny. I met this guy and he's ok.. I don't think I'm interested but I dunno, what do you think? I think, I mean, he's ok enough, but he has big ears and he's sort of stiff and all that but I think I'll call him.  Yeah. I think so don't you? When should I do it?"

Me: "Uh huh."

G: "What?"

Me: "You should have fun..fun fun!  Call him."

G: "Totally — that girl had a nice bag."

Me: "What girl?"

G: "The girl who walked past.  Didn't you see? I wonder where she got the bag from."

Me: "What? Which girl? Where? – Oh the one over there?  Turning the corner?"

G: "Yeah."

Me: "She's fat dude. I thought you were talking about someone hot."

G: "So that's why you didn't notice.  Her bag was nice."

Me: "Ok, whatever."

G: "That guy was sorta cute though."

Me: "Which guy? Where are you looking – when are you checking out these people???"

G: "The guy who walked past a while ago.  He was sorta skinny but I like that punk look."

Me: "Uh.  Dude, I'm totally missing all of this. How are you checking these people out?  Your eyes aren't even moving! You girls are nuts."