Welll...in our statistics when added to one attempt plus an otherwise good sway, it seemed to improve results by about 5% but that doesn't mean that it really raises odds of pink success 5%. MOst people were not doing immediate J and D but instead after 5 minutes and it may not be appropriate for everyone.
I just do not want anyone to read this and now think "jump and dump adds 5%" it doesn't.
Exercise needs to be 60 minutes. 50 is not enough