I bow to greater experience. I was simply repeating the advice given to me by my dearly beloved resident expert, advice that did get me out of trouble when I was on the brink of despair. I did, in fact, overstate the advice about moving the fabric with the tension arm not fully up. What I should have said is "don't do anything that pulls on either the upper or lower thread unless the tension arm is fully up." Readers are advised that Ramblin' Rev's advice trumps mine.