Not original, unforynately I'm afriad. HPC make this tool already.
I experimented with this by doing something similar to what you suggested, and hung fishing weights to it.. it worked ok for locks without security pins, but filed spectacularly when I tried to beat spools, and mushrooms.
It lost me the feedback I get from the tension wrench, and since I et little from my pick this mant about 80%.
I'm not putting it down, but I don't have much nice to say about the weited tension idea.
Good thought though.
