disassembly of Debug.exe?

Based on postings and responses to othes, I wondered about finally
fixing the problems that irked me about MS Debug.exe not including a
function to trace out code vs data and allow simple dumping of
assembly code. And this is an itch of some 20 odd years!. But now I
have more time (huh!).

So I set out to disassemble Dbug.exe to add a full listing ability.

What surprised me was that NONE of my fairly-useful disassemblers
(BUBBLE, DASM, DIS86, GRDB, IDA, SICETOOL) would succeed!

Bubble managed to give me a page by page list, but it was pretty much
the same as using debug itself; (the tedium!), the rest simply bombed
out! Yes, really!

All of these tools are extremely difficult to use anyway.
Usually there a two requirements when using a disasembler:-

a) step through code to find a problem and hence a solution.
b) disassemble everything to study principles, suitable insert points
for additional services,
change nature of functions, all usually to make a better tool.

What do the readers suggest in either category, (but especially "b")?

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