I think I had underestimated the work involved in heating and bending a spring, last night I watched a vid on YouTube of a guy practising the process which showed some interesting results, the only difference being that I didn't intend heating the hole spring as he did in his tests.
When he heated the whole spring to red hot and allowed to cool slowly the spring lost most of its memory, so when stretched a fair amount it stayed in that position but didn't break.
I only intended to heat a small area so I could rotate the last coil up to a flatter position, I'm not sure what difference it will make to the spring if it looses some of it's spring memory over say 1" of the springs total length.
I have a new spring on order, I'm just thinking out loud as the saying goes