Blocking Surface & Landmarks

[rookie]

I have a lot of DVDs, documents, etc. on blocking technique. But, I'm STILL a little unsure about shoulders vs hands & the landmarks for hat & hands, etc. I've never felt completely comfortable with how I've taught it.
I have DVDs and such where coaches say things like "hat at the level of the DLs belt buckle"...then watch the video of their team, and the players are no where near this.
So, what do you teach - shoulders or hands or a combination ?
Also, what are your landmarks (let's say for a down block) for your blocking surfaces & hat ? Thanks.

[Coach Metz]

Hey Coach.
I teach helmet at belt buckle height, and I get the same result. My main goal is that my linemen get lower than the defense. I've always exaggerated aiming points to get them to do it where they go. In the end, if my guys are lower than theirs, I'm happy.

[mvp]

I agree with Coach Metz. I've been coaching OLine for 16 years now and we use belt buckle or hip aiming point as well. Being in Texas we have a little more freedom than some cutting, as well. Our goal is to be mean, nasty, low, and viscious.

[Coach Metz]

"mean, nasty, low and vicious" ... love it!
I have to agree, I like it when my O-Line has a case of the nasties!