Janome website http://alturl.com/meh83 has this posted:
What is the best way to unthread my sewing machine? -Anonymous
Dear Anonymous,
Always cut the thread at the spool and pull the thread through the needle and out of the machine. If you remove the thread by pulling on the spool, the thread can easily get caught, affecting the tension as you pull. Lint from the thread can also cause the needle to bend at the tip, resulting in snagged fabric or inconsistent stitching.
Truth be told, I just started snipping the thread at the spool and right before the threaded needle. Then with the foot raised, I pull down/forward slowly.
This is similar to the way I change thread on my longarm machine.
Nan - Indiana