My instructor said that my shoulder was going to high when I did bong sau in single sticky hand. He said that the shoulders should stay level with each other when doing this technique but I found this impossible. He blamed the weights, is this all correct?
When the shoulders come up they lose the connection to the rest of the body and power is lost , in any movement you should be striving to keep the shoulders relaxed and down.
It could just be a shoulder flexibility issue related to the weight training or could be due to an old injury , I know with my left elbow strike it does not come up as high as the right because I injured it years ago helping a young lady move house.
There's not much you can do about it except be aware of the problem and keep working on it .
My advice to you would be to get in front of the mirror and practice loosening up the shoulders with what my master used to call the "chicken wing exercise" , its supposed to be an exercise for elbow strikes but it should be of benefit to you.
Keep your fingertips of both hands high on your chest as you make big circles with your elbows , make the rotations as big as possible , do quite a few repetitions then reverse the direction.
After a few minutes of this the deltoids will begin to fatigue and start to relax , next give your arms a bit of a shake and let them hang down limply from your shoulder sockets , concentrate hard on relaxing the shoulders and letting go of any tension , feel the weight of your arms pulling your shoulders down.
Next bend your arms to the approximate angle you use in chi sau and with your elbows pointing down by your sides start to scribe small circles with your elbows first one direction for a while then the reverse direction , all the while concentrating on letting the arms hang from the socket and keeping the shoulder joint as relaxed as possible.
Next you might want to practice rotating from Tan to Bong and back again still maintaining the feeling of the earlier exercises in keeping the shoulder relaxed and down.
Then start practicing your chi sau with a partner and still concentrating on your shoulders.
These exercises should give you some degree of body awareness so that you can recognise those times when you are tensing up and raising your shoulder , which is half the battle really , recognising when and where the tension is located and then consciously relaxing the area.
It's just going to take a little mental discipline for awhile thats all.
With the weights I would avoid isolation movements such as bicep curls like the plague , you want to get more into things like the bodyweight stuff Geezer mentioned , stuff like pull ups , chin ups etc .
These give you more functional strength anyway , as more muscles are recruited and worked through different planes of motion.