If you don't mind me asking: Do you (a) harden your brainwallet using a script, similar to OP, or do you (b) rely on a technique that you can apply off the top of your head, without relying on a computer? (eg. a long passphrase that is not part of a known body of literature, changing / shifting letters around in a way that can be easily remembered...)
Both make sense when trying to avoid storing data outside your head, but (a) seems more secure while (b) gives you full flexibility regardless of whether you have access to your hardening script.
Both make sense when trying to avoid storing data outside your head, but (a) seems more secure while (b) gives you full flexibility regardless of whether you have access to your hardening script.
What does it matter?
However I hardened my passphrase, I'm not going to unharden it now by telling you about this.
Although (brain wallet produced by human) --> seed key
is recognized and accepted as a bad idea,
f(brain wallet produced by human) --> seed key
where f is a easily remembered math procedure such as modulo(x), may form an acceptable key