Im speaking about ditching a few pounds at depth (for whatever reason if needed). I was trained to never ditch your weight belt unless you are at the surface.
What's the "for whatever reason if needed" that would cause you to need to "ditch a few pounds" at depth?
Your instructor sounds like he may have been lazy in doing your weighting (at worst) by slugging it all on your belt or (at best) he/she simply wasn't being clear about a few different pieces of advice:
- There are very few situations requiring ditching weight at depth.
- If you do need to ditch weight at depth, you don't need to ditch much to establish buoyancy (assuming you were properly weighted) in the first place
- Ditch your weight at the surface if you need to establish positive buoyancy
- If you carry a lot of weight, don't put it all on your weight belt (or any one place) because if you lose it at depth you could be in trouble
So it's sort of easy to see how all of those things might be jumbled up and read as also conveying "only ditch your weight belt at the surface" and/or "never ditch your weight belt at depth."