Wow! Thanks SO much to Daniel (and John and Rishi as well!) for your comments and suggestions. They are ALL very much appreciated.
Daniel, I understand your points and agree 100% with everything, however I still have a few "nit-pick" things to figure out (and if you look at my original / conventional DL I think some of the SAME bad habits are also in the Sumo--or maybe I'm just too critical of myself??)
1) I STILL cannot seem to get that "hip hinge" movement that's SO important in ANY style of DL....how do I know (feel) if I am doing it properly? I have seen a LOT of videos where the guys just over-exaggerate the LEAN back at the top of the movement--which I know to be IN-correct in terms of assuring that the hips were involved.....ALSO....I have seen where guys get their butt WAY down (like a squat), and initiate the pull from that point, BUT again I understand that at the very moment of starting the pull there is a slight "upward tilt" at the hips which causes the butt to move away from the floor. I have watched a lot of different guys on YouTube, and the vast majority lean back while taking up the slack on the bar, almost nobody initiates the PULL from an "ass to grass" squatting position! Do you guys agree??
2) Daniel, I completely understand what you are saying re : "resetting" for a moment at the bottom of each rep, but on my original DL video I was "roundly criticized" by a certain (pedantic) individual who seems to always "have all the answers"; he wrote that I should NOT relax at the bottom (eccentric), but actually KEEP the tension through ALL the reps UNTIL finished?! So now I'm in a quandry--since my training partner ALSO says that I MUST be controlled through ALL the reps, and just take a VERY soft "touch" on the floor (like I did here)--but maintain tension for the next reps. For sure that slow eccentric DOES work my lower back, and I'm happy to be a bit more "relaxed" by dropping the BB from knee-height (no problem at my gym), then re-grip / re-set and initiate a "fresh" pull for each rep....but in doing this am I "cheating" myself out of TUT, or am I simply "protecting my 52 year-old back", ha ha!! Opinions?? I felt SOME sore-ness in the lower back for the rest of the day (equally on both sides of the lower lumbar spine), but today I feel fine. And this was my FIRST Sumo lifting experience (5 sets x 10 reps + a few extra for this video)
3) As for getting the bar closer to my legs / shins...Daniel was very perceptive, as this video was made after all my working sets (starting at 75KG, progressing to 90 KG), but during one of the sets I did a nice scrape on my right shin, with the normal blood trickling down.....I guess I'm a "real man" now? I must have subconsciously moved the bar AWAY from my shins a bit for this video--in order to avoid further wounding my legs! I guess I need to be more careful, or apply tape before doing these next time!
So to summarize : Should I NEVER do conventional DL's again, and concentrate on Sumos from now on? And, would it be wise to REDUCE the weight a bit in the coming sessions just to REALLY concentrate on getting that "hip-hinge", and outward knee bend? Again, my trainer wants to "push" me to my full potential (he's 40 and looks like a rock, but of course has been lifting for years and years), so he's big on progressive overload, etc....but with these compound lifts there is potential for injury (and not so easy for him to spot me in case of a failed lift), and I do not want to suffer an injury in the process of "learning" DL's and squats....
By the way, I am trying to do DL's twice a week and never on the same day as squats (also done twice a week); normally I do 4 or 5 sets, with 10-12 reps per set. At this early stage in my leanring compounds, I have also read that perhaps it's wiser to do HIGHER reps ranges (12-16 reps--with lower weight if necessary), just to form the motor-skills and necessary nervous system adaptation.
Sorry to be so long-winded....as much as I like all the great info on this site I am also learning a lot by watching videos of other people actually TEACHING the lifts and making corrections on a new lifter; this is also very useful to me, and if anybody has some good video links for that I am always appreciative for those resources.
Thanks again!
Harley