I am an expert in this process. I do it day in/day out, on some very sophisticated circuits. I have a programming and maintenance certification on Palomar (formerly Hugh's Aircraft) 2460 and 2470 Mark III bonders. I've forgotten everything I ever knew about programming, but I wasn't too bad at the repair part.
First, define dummy bond. I am familiar with ball bonding, wedge bonding, chisel bonding, ribbon bonding, security bumps, and prebumps, but I've never heard of a dummy bond. I am also very familiar with bond pulls and ball shears to measure quality bonds. I don't have much experience with aluminum wire, but I have used 0.7, 1.0, and 3.0 mil gold wire for quite a few processes.
With conventional ball bonding the clamp grabs the wire and breaks the tail off at the substrate to set up the EFO for the new ball. I am old enough to have worked with and on honest to God hydrogen torches, which did not break the stitches off, you had to pluck the wires after you were finished, this was TC (thermo compression) processes as opposed to EFO processes, which use ultrasonics at 128KHz and electronic flame offs.