Cinderblock - if starting from hershyzer you need to windup more before starting forward move. Bend knees and hips turning your butt further back and bringing your head further back. Try to keep your rear toes on the block after stride and planting.
Double Dragon - looks flat footed and feet spinning out. Need your feet more plantar flexed and toes digging into the ground to resist them spinning.
Throws stride looking better with feet closer together. Your shoulders are rather flat/ horizontal, so you could coil more vertical.
Maybe a slight kickback in the windup on the cinderblocks to help him connect it to DD?
Had a couple DD "discoveries" the past few days I thought I'd pass along in case it causes anything to "click" for
@Kjimsern. I am continuing to do it daily to get more reliably athletic on my feet as part of my rest days.
Day 1: got more on balls of my feet, move felt uncertain, noticed that my knees (plica) were a little irritated going each way w/ the lateral part of the move. I think that's part of why my brain resists getting more athletic.
Day 2: same approach, move already felt more stable, knees already less cranky. Balance was adjusting.
Day 3: added more momentum, no noticeable knee issues, starting to feel more comfortable with momentum. Definitely easier to get more plantar flexed. Something still seemed missing.
Day 4: read
@sidewinder22's comment about toes digging into the ground. This AM paid more attention to my toes. I was on the balls of my feet/plantar flexed, but toes weren't really helping grip the ground like they do when walking. As soon as I changed it, it made my whole move more robust, quicker, more stable, and my legs felt like they do when I'm boxing. Athletic and strong but quicker and springier. Had trouble keeping it going each way with the arms moving at first so I backed up to Can Can drill and really focused on letting toes grab the ground and whole body moving with lots of momentum. Legs got more stable and momentum and "X-factor" improved. Was able to sustain better in DD right after exaggerating toes grabbing ground with Can Can and letting my body get coiled up by leg momentum each way.
Suggestion: if the North-South balance is challenging and body isn't taking the hint, take arms out of it with Can Can & fix the legs in balance, then add arms again.