Right. The only major mail system that pays attention to SPF is Hotmail, but there are enough small poorly run MTAs that use it that an SPF record which lists your outbounds and ~all (not -all) can be marginally useful to avoid bogus rejections of your mail.
For example : [ various large ISPs that publish SPF ]
Perhaps this is a language problem. In English, "publishes" is not a synonym for "pays attention to." As I said, you need to publish SPF to get mail into Hotmail. That's why people do it.
I know there is a problem so far with forwarded emails but there is also a solution : [ hoary SRS proposal to change every SMTP server in the world to make them match what SPF does ]
Sigh.
Every time a mail arrives that is an SRS address the password and timestamp could be checked, and faked or outdated recipients could be rejected.
You might want to look at BATV, which has nothing to do with SPF, but I have found is quite useful for recognizing spam blowback. R's, John PS:
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