I didn't go that far though that design is not new to me. To keep my inventory of equipment down I just clip the bag shut with a small SS clip, which also holds the piece of string that keeps the bag somewhat suspended.
When adding hops I just use tongs to lift the bag to the edge, where the clip holds one side of the bag's opening to the lip of the kettle. I'm then free to stretch the bag wide open with one hand while I dump the hops in. Then it's clipped shut again and released into the wort.
Takes less than 10 seconds to accomplish and my schedule of 60-45-30-15-10-5-1 goes off without a hitch.
I don't insert the IC until flameout. It's already cleaned and sanitized and just plunging it into the wort will drop the temp about 10 degrees. Thusly, no problems with the IC interfering with my hop's exposure to the wort and no contamination either.