Can I use sqitch-rework for non-idempotent changes?

Question

After reading the sqitch-rework documentation and the Altering Table with Sqitch Rework command stackoverflow question, I am aware that sqitch-rework was intended for idempotent changes.

But why?

It seems that my use of sqitch-rework works perfectly fine with a non-idempotent change.

Here is how I used it with PostgreSQL:

original deploy:

-- Deploy myproject:database/facility/schema/public/table/mytable to pg
-- requires: database/facility/schema/public

SET ROLE :"owner_role";

BEGIN;

CREATE TABLE public."MyTable"(
  "Date" timestamp without time zone NOT NULL
);

COMMIT;

original revert:

-- Revert myproject:database/facility/schema/public/table/mytable from pg

SET ROLE :"owner_role";

BEGIN;

DROP TABLE public."MyTable";

COMMIT;

reworked deploy:

-- Deploy myproject:database/facility/schema/public/table/mytable to pg
-- requires: database/facility/schema/public

SET ROLE :"owner_role";

BEGIN;

LOCK TABLE public."MyTable" IN ACCESS EXCLUSIVE MODE;

ALTER TABLE public."MyTable" RENAME COLUMN "Date" TO "Complete time";

ALTER TABLE public."MyTable" ADD COLUMN "Start time" timestamp without time zone;
UPDATE public."MyTable" SET "Start time" = "Complete time";
ALTER TABLE public."MyTable" ALTER COLUMN "Start time" SET NOT NULL;

COMMIT;

reworked revert:

-- Revert myproject:database/facility/schema/public/table/mytable from pg

SET ROLE :"owner_role";

BEGIN;

LOCK TABLE public."MyTable" IN ACCESS EXCLUSIVE MODE;

ALTER TABLE public."MyTable" DROP COLUMN "Start time";
ALTER TABLE public."MyTable" RENAME COLUMN "Complete time" TO "Date";

COMMIT;

Am I not understanding something? Isn't this a valid use of sqitch-rework?