I've attached a patch with documentation for the RubyVM::InstructionSequence class. It's of decent size, and I'm just getting familiar with the VM, so please send comments and corrections if you have any. I'm happy to do further passes if need be.
This issue was solved with changeset r36525.
David, thank you for reporting this issue.
Your contribution to Ruby is greatly appreciated.
May Ruby be with you.
iseq.c: Added documentation. Patch by David Albert. [Bug #6785]