Re: Safety amongs beginners
I, too, have been in the same situation on many occasions, and I've learned the painful way to respectfully refuse to train with individuals who, for lack of better words, are strangers to self-control and balance. There are two sides to this problem, though - the risk of injury to the individual him/herself, and risk of injury to training partners. I was unfortunate to be put in the position of teaching Aikido (as an assistant instructor at my local club in England) to my younger brother, who has the coordination of a stunned cow, and I still, to this day, do not know how either of us survived it! He quit after 6 months because he managed to break his ankle, and was never able to perform a safe, simple mae ukemi from seiza (he would try to do mae ukemi from standing by sticking his arm in the air, then throwing it at the ground, hoping his body would follow - several times, he would cross his legs as he went over, causing his thighs to act as nutcrackers on a certain part of his anatomy - I still have sympathy pains when I think about it). He was very dangerous to himself and everyone on the mat, and we had to make sure that he practiced with the more experienced students who could look after themselves (and him!)
It is good that your sensei is keeping a very close eye on this student, for the student's sake and those around him/her, as this can detrimentally affect everyone on the mat.
Good luck when you test for yellow belt!