Not saying you should not do what you are thinking, but .....
Did you realize that you can use machine embroidery thread for quilting?
I have used the Hemingworth brand on several quilts, for both FMQing and straight line quilting.
No problems!
It gives a nice glisten from the shine of the thread.
The fineness of the thread makes any mistakes less visible (that I choose not to correct).
Just a thought ...........