My taste says that an empty or absent Subject: is valid, and should not be forbidden or "corrected".
I agree with the proposed change, to reply to an empty Subject: with
just "Re:" (or whatever, if that reply-marking string is configurable).
- Re: [PATCH] Change hardcoded subject of rep... Derek Martin
- Re: [PATCH] Change hardcoded subject of... Eike Rathke
- Re: [PATCH] Change hardcoded subject of... Maxim Tarasov
- Re: [PATCH] Change hardcoded subje... Vincent Lefevre
- Re: [PATCH] Change hardcoded subject of replies Eike Rathke
- Re: [PATCH] Change hardcoded subject of replies Maxim Tarasov
- Re: [PATCH] Change hardcoded subject of replies Aaron Schrab
- Re: [PATCH] Change hardcoded subject of replies ilf
- Re: [PATCH] Change hardcoded subject of replies Derek Martin
- Re: [PATCH] Change hardcoded subject of replies Maxim Tarasov
- Re: [PATCH] Change hardcoded subject of replies Kurt Hackenberg
- Re: [PATCH] Change hardcoded subject of replies Eike Rathke
- Re: [PATCH] Change hardcoded subject of replies Kevin J. McCarthy