[trentgreene]

Heh, ‘drop’ is an overloaded term. I don’t mean you need to release the bar from your hands or not follow through on the eccentric. By ‘drop the bar’, I mean you shouldn’t resist during the eccentric portion in the same way you might during a pull up or curl. Said another way, on heavy deads, your eccentric should be noticeably quicker than the concentric. The bar falls to the floor with you attached.

The other commenters explain why — you’re building up fatigue during the concentric, easier to over round on the eccentric if you resist.

It’s worth caveating to that there are many ways to pull, and I could imagine someone lightening the weight to resist and control the eccentric. But in the the style of pulling I grew up with, a set of 5 reps functioned more like 5 heavy singles in a row, with some seconds of rest and resetting form between pulls. I’ve never seen controlled and resisted eccentrics with that style, and the thought of it lit scares me.

PS. Pulling 455 means that you almost certainly have some expertise in this matter ;). That’s not an untrained pull