Two suggestions that might make it easier for you. There's a package called `undo-fu` that puts a thin layer on top of the undo system to keep the behavior stri

Two suggestions that might make it easier for you. There's a package called `undo-fu` that puts a thin layer on top of the undo system to keep the behavior strictly linear. And built in, there are the `undo-only` and `undo-redo` commands. Unlike the base `undo` they will only walk in one direction.