"Distinct Logins" and etc is actually the number of distinct identity cookies the web server recorded that day
.........A DISTINCT..........
...... IDENTITY COOKIE........
Technically speaking, logging in and logging off only affect an identity cookie stored within your web browser.
Which brings up a bit of a misnomer in the back-side statistics. "Distinct Logins" and etc is actually the number of distinct identity cookies the web server recorded that day. Which is why the number continued to climb at a pace which exceeded other statistics: often, people create an account, log in, get the identity cookie, post a message, and then go back into lurk mode for weeks or months. Other than demonstrating this effect, "Distinct Logins" was pretty useless. As most of the back-side statistics proved to be.
The difference between front-side and back-side. Front-side is the first Free Republic program your web browser contacts. The front-side valiantly defends the back-side from becoming swamped by attempting to satisfy your request by consulting it's massive cache of documents. However, should the requested document not reside within the front-side's cache, the front-side can do nothing else but to pass your request to the back-side (from which it will often remember the page in order to satisfy subsequent requests.)
If you're still following, it should now be obvious that the back-side didn't see enough of Free Republic traffic to accurately report statistics. And hence, the discontinuance of the back-side statistics.
Also, since the front-side is a very efficiently designed web server, it is not very expensive (CPU resource wise) to trickle down a 500Kb post over a 28.8Kbps connection. If that takes 10 minutes, it does not bother the front-side. The front-side should easily be able to handle thousands of such requests simultaneously.
OTOH, the back-side is far more limited in the number of requests it can serve at once. 65 at the moment. And each one is piggy. The front-side acts as an intermediary, quickly slurping everything the back-side has to give, as fast as the back-side can give it, in order to free the back-side to handle another request. The front-side can then trickle this down to the browser without bothering the back-side again.
And there you have it. More than you ever wanted to know about the technical matters of Free Republic. I should write a book.