One of the often touted features of Google’s GMail is “conversation view“. In Google’s own words:

Gmail groups all replies with their original message, creating a single conversation or thread. In other email systems, responses appear as separate messages in your inbox, forcing you to wade through all your mail to follow the conversation. In Gmail, replies to replies (and replies to those replies) are displayed in one place, in order, making it easier to understand the context of a message — or to follow the conversation.

Sounds pretty good, doesn’t it? Well, maybe if you don’t know any better it does. The trouble is that Google – like so many other email client/service providers – have all but abandoned the real message threading capability that is present in all email that adheres to RFC 2822.

RFC 2822, which defines the standard for what most people call “email”, was published in 2001, a good three years before GMail came along. But RFC 2822  superseded RFC 822 which was published in 1982. Then again, RFC 822 superseded RFC 733 which was published in 1977. It is within RFC 733 that we find the following in section IV.B which describes some of the optional header fields:

1. Message ID
This field contains a unique identifier (the phrase) which refers to THIS version of THIS message. The uniqueness of the message identifier is guaranteed by the host which generates it. This identifier is intended to be machine readable and not necessarily meaningful to humans. A message identifier pertains to exactly one instantiation of a particular message; subsequent revisions to the message should each receive a new message identifier.

2. In-Reply-To
The contents of this field identify previous correspondence which this message answers. Note that if message identifiers are used in this field, they must use the mach-id specification format.

Although optional, if we wind forward to RFC2822 again we find the following passage which refers to these fields in section 3.6.4.

Though optional, every message SHOULD have a “Message-ID:” field. Furthermore, reply messages SHOULD have “In-Reply-To:” and “References:” fields as appropriate, as described below.

If you’re a GMail user, open up any email that is a reply to another and on the top right corner of the mail, click the arrow and then ‘Show original’. You will see the full text of the email message, within which you will see the above two fields. If you make a note of the “In-Reply-To” value (I suggest copy and paste it somewhere) and then find the original email that was replied to you should find it matches that email’s “Message ID” value. It’s that simple.

When I first began using email, I had a 1200 baud modem which I connected to my ISP only when necessary. During those connections a UUCP (Unix to Unix CoPy) conversation took place which downloaded emails from the ISP, uploaded any pre-typed outbound emails and also got my Usenet newsgroup subscription messages. The World Wide Web may have existed at the time, but it certainly wasn’t in popular use.

At that time I used an email/news reader written by a chap I knew. It had “thread by reference” as a standard feature. This mode of threading email conversations simply matched up the “Message ID” and “In Reply To” values to create a true ‘conversation’ view. Some years later I purchased a Mail User Agent (MUA, also known as an email client) called “The Bat!” which you can still buy today (for MS Windows). It also, unsurprising to me at the time, has a “thread by reference” view. Then came GMail, and a giant step, well, sideways.

So what’s wrong with GMail’s view of ‘conversations’?

1. If you change the subject, the conversation splits. GMail offers an option to “Edit subject” when you reply to an email. If you take that option, your reply will not thread with the original message.

2. If you receive two or more independent emails with the same subject line, they ‘thread’. A typical example is notification type emails. I receive notifications when certain things happen on some of my web sites. If I get 10 notifications, there is one GMail conversation and it takes me a little while to notice this because it only takes up one line on the GMail display.

If Google just did what they do and didn’t frequently sell this feature I might just let it slide. After all, The Bat! does also have a thread by subject mode if I remember correctly. But they do sell this ‘feature’ as an advantage of GMail.

I want to know why the tech world – who should know better – are buying this sales pitch. Too much ‘Google Juice’?