Conversations not grouped by subject in El Capitan mail

I already made a report at http://www.apple.com/feedback/ . As I said earlier, I've heard that Apple actually acts on those reports, though they guarantee no feedback about them.

I haven't tried https://bugreport.apple.com/, except to get logged in. It requires a developer account, which is more than most people want to do, but it does let you see your bug reports, and, I would assume, Apple's responses.

https://getsupport.apple.com/Issues.action appears to be a way to invoke your support agreement on purchased products. If you're still in warranty or AppleCare on your Mac, you might get some help there.

What is your experience, Jacqualine, with contacting Apple by these three different methods.

I submitted an enhancement request through https://bugreport.apple.com/, asking for a preference to restore the old behavior. There appears to be no way to share those reports with other non-Apple people, but here's the text:

WILLIAM ST CLAIR 08-Oct-2015 05:43 AM

Summary:

I get Fail2Ban mail from my web server, including the IP address of machines that provide bad credentials to my WordPress site. Before El Capitan, Mail would group all of the messages with similar subject lines ("re: foo" was grouped with "foo"). Now it uses some other algorithm, probably actually following chains of messages through other headers. The new behavior is actually more "correct" than the old, but the old is often useful. Evidence this discussion: https://discussions.apple.com/thread/7252086

Steps to Reproduce:

1. Get two different email addresses. I used my gmail account and an account on the machine with Fail2Ban installed, which I read through Apple Mail. I'll call them sender and receiver below.

2. From sender, send a message to receiver with the subject "Test conversation grouping", and the body "Thread 1, message 1".

3. From sender, reply to the message in 2, with the body "Thread 1, message 2".

4. From sender, send a new message to receiver with the same subject as in 2, and the body "Thread 2, message 1".

5. Get receiver email with Apple Mail

Expected Results:

One conversation with subject "Test conversation grouping" and three messages: "Thread 1, message 1", "Thread 1, message 2", and "Thread 2, message 1".

Actual Results:

Two conversations, both with subject "Test conversation grouping". The first conversation has two messages: "Thread 1, message 1" and "Thread 1, message 2". The second has one message: "Thread 2, message 1".

Notes:

The new behavior is probably the right default. There actually ARE two conversations. But I'd like a preference to use the old classification scheme, that used only the subject to group conversations, and resulted in the "Expected Results".

Configuration:

In El Capitan, I get the "Actual Results". In Yosemite, I get the "Expected Results".

Apple closed my bug report as a duplicate of another, still open, bug. Seems there's hope that they will fix it.

Not sure where we'd get news, except to notice a new version of Mail.app that fixes it. Apple has closed my bug report. They gave me a number of the one that mine duplicated, but there's no way for me to view that bug. They apparently pay attention to http://www.apple.com/feedback/, but they don't reply, only act, or not.