Sylvain Hellegouarch wrote:
> 
>> I have no idea what you mean by "not precise enough to be used". What
>> makes them imprecise?
> 
> The very fact they don't represent a state that can be trusted. As the
> spec says they are not the true value but the true value at one given
> time.
> 

The values are no more or less trustworthy than the link's own type,
length, and hreflang attributes.  I refer you to
http://www.w3.org/2001/tag/doc/mime-respect-20060412

>> Look at just about piece of blogging software that accepts comments and
>> on the front page you'll typically see a link that specifies the number
>> of comment received for that entry.  It may, or may not be an accurate
>> count, but it serves a useful purpose. Why is the same metadata not
>> useful in an entry/feed?
> 
> Well to take your example a bit further. Say I'm following comments posted
> to an entry, since there is no way for me to decide if the number provided
> by the extension is the most up-to-date, I will have to manually go to the
> source itself and check if someone replied since my last visit. How is
> that useful to me as an user?
> 

If you need an exact count, go to the linked resource. Feed publishers
should take steps to ensure that the count is accurate. Again, read the
W3C Tag finding referenced above.

> Besides you do not answer the question of HTTP caching I mentionned.
> Basically it would break most planets out there which rely heavily on the
> '304 Not Modified' status code to check if a feed has been modified. In
> this case a server such as Apache would respond: "well yes the file has
> changed on the disk so here it is" when in fact the content of the feed
> has only changed for the number of comments of an entry.
> 

HTTP provides a possible solution to this in the form of a weak entity
tag.  Also, Feed delta encoding could be leveraged to further mitigate
the potential issues.

> Clients could of course work around such issue but this is a rather big
> problem to me.
> 

I would suspect that you currently have the same problems with folks
that use the highly popular slash:comments RSS extension. FTE is not
introducing any new problems, nor is it seeking to fix existing problems
in the feed syndication model.

- James

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