If you can't find someone who can demonstrate it, I'm afraid you are going to struggle. The other problem is that you will probably need to take your technique apart a bit, and you will get worse before you get better. Maybe not the best idea if you are looking to grade soon. I'm sure the IS/IP guys know a lot more than me that can help you, but there is not much that anyone can do to help over an internet forum.
Not sure how IS/IP is going to help in this case. Usually when the strength bogey man comes up it really is code for fluidity and a concentration on what might happen rather than the technique itself. It is also - I have to say - another one of those terrible words like "relax". Lot's of meaning but not particularly helpful.
One thing that can work is to remove the partner out of the equation. Practice your technique at home with an imaginary friend but keep in mind the vectors and other concepts important to what you are trying to achieve. Probably wont help you in the weeks leading up to Shodan there are no quick fixes but in the long term it is a useful exercise.
That said - everyone I know always degrades just before Shodan in their own mind and others. The best answer really is not to worry too much about it and train as you did before you got the nod to test. Usually if you get that you should be good enough to pass.