Marc,
I have a bombax that looks exactly like yours did (only one stem, though) and I was thinking of pruning it like you did to encourage a more squat shape, bigger caudex, and not let it get tall. I am encouraged by your results, it looks great! any tips? I am a "neophyte" at this. can you get the part you cut off to root as well? what would be a good time of year to try this operation(I'm in arizona, HOT summers, mild winters).
wonderful photos.
Alan