I use them for strength, explosion, and trap/back development. Generally they fall on back day if I train them heavy or they can be done after legs or with shoulders. Results are fantastic. No exercise builds traps like these lifts.
Get someone very knowledgable to train you in this lift. All the muscle mags show dumbass bodybuilders doing them improperly - in a demonstration no less!!
There may be some technique websites - if no one posts one search yahoo under weightlifting or a variation including olympic.