Great posts thus far.
In my oversimplified view of the two methods: ramping pushes maximum strength in the rep range that is trained while sets across build up the work capacity and volume from which max strength rests upon. In the context of a pyramid, ramping pushing it higher while sets across widens the base. There is obviously cross over, but one is better at its task than the other.
Probably best for beginners and some intermediates to use mostly sets across as it helps develop a greater capacity for work with a greater volume of heavier weight. Sets across also don't change, this is obvious, but in a movement that the lifter is still learning or attempting to master its important to keep the stress the same or very similiar for each of the working sets. From set 1 to set 3 - 5, the lifter knows what to expect and more importantly leverages don't change on account of the weight. This allows for "easier" learning of the lift with a decent amount of weight.
For higher skilled intermediates and above, the lifts are more than likely mastered or performed consistently regardless of weight on the bar. From there it would be a better option of pushing strength through higher intensities which would be accomplished by ramping up to a top set. Aside from strength, working to a very heavy set builds confidence with heavier loads and further improves the efficiency of reps at high intensities.
Some type of "volume" stimulus is needed by all levels of lifters to support their max strength and build it up further. For beginners and early intermediates, this is already accomplished by volume provided for the sets across. For more advanced lifters, volume can added in many ways, but usually in some form of sets across. This volume can be performed right after the top set with sets across. For those following some kind of periodization this might also mean several weeks of building up to heavier volumes with sets across before tapering down and focusing on high intensities, using ramping sets.
For more advanced lifters the volume and sets across can be added through assistance work as working up to say a 650lb squat already provides a tremendous amount of volume on the mainlift. In such cases, I've seen many lifters either just do one down set for higher reps (which is still heavy and adds a lot of tonage) or move onto less stressful lifts for higher volumes.
My take anyway...
Last edited by Pull14; 02-09-2012 at 05:05 PM.