Yes, I've trained multiple people who were stuck on the chinups with weighted chinups.
Here's the deal: Let's say he weighs 90kg. He can do 5 reps with 90kg.
Do you think adding 2kg to that is gonna make him miss the fifth rep?
Unlikely, he can probably do 5 reps with 4kg or more even.
So he starts small and on every workout he increases the weight by a small increment (2kg at first, 1kg later on).
Give a month or so and he will be doing 3x5 with +-20kg easily.
Take the weight off and he will be able to do 3x12+ easily.
Progressive overload really is a magical thing, isn't it?
>I just want a simple mobility routine specifically for high bar squatting
90% of the problems are fixed with ankle stretching/mobility work and wearing weightlifting (heeled) shoes.
Most people prefer 2cm heels, but if you have bad mobility you can go with heels as high as you like. There are shoes sold with 2.5-3cm heels, and you can also add heel height with a cobbler (pic related).
For ankles, there's lots of stuff here youtube.com/watch?v=XISJxsccN1E
>Also something to fix lordosis
This requires physical examination. Better finding a professional.
>FAGS
Widen your stance if it's too narrow.
Angle your feet and shove your knees open when descending, so that the knees track over the toes (use a resistance band or something elastic around your knees if you have issues with this).
And do warmup sets. Don't skip them.
This fixes the issue 90% of the time.
If your tendons are currently inflamed, let them rest and cool off for a few days.
If you're 100% sure your knees are tracking over your feet and they're angled properly (post vid), and you're still having issues with this, then start stretching your posterior chain and hip rotation.