I can't find that rowing video.
I don't do a SLDL with perfectly straight legs because I think it places the lower back in too precarious of a position.
I see, you do your SLDL much like Yates did his, in fact it looks like a carbon copy, and you have great back development so you know what you are doing. Now, if you watch Ronnie do his SLDL he keeps his legs straight, and that's the way I prefer to do them, I can "feel" it much more in my hamstrings, but I only use 245lbs for my final set, much different than 455.
Also, a shame you can't find the BB row video. The BB row is my favorite exercise.