I've lost count of the number of posts I have written on this site only to find that the data capture has failed. It is so annoying to spend 10 minutes writing a message, entering the number or letters that match the squiggly capture picture, only to find that the data capture failed. Please get rid of it, what point does it serve? or at least detect the data capture before writing a message.
Has anyone else had this experience.

Yes - many many times !!! ( Some people are going PHEW !! )

yes..so I always "copy" my copy before I post in case that happens. Saves a lot of time.

I copy my posts too, because it's caught me out a few times. I understand what it's for, but I don't see why the digits have to be disguised, so I keep refreshing until I get some that are readable, then hope for the best.

The reason is to stop SPAM.
Without it we used to get hundreds of stupid spam posts a day which took ages to delete.

As Denise says, usually refreshing until you get one you can see works.
Then there is the "copy and save": trick.

Sorry, but it is needed.

And registering is a good idea.

Usually with these things it's the difference between O and 0 - that's an o and zero.

Try to avoid them by refreshing.

The capcha thing has to be unreadable to an extent to stop computers scanning the image and deciphering the characters.

Registration is a convenient alternative - I can say I've never received any spam from doing so

It's also the 1 and I, the g and 9, the 2 and z.

Once I got all three digits on top of each other.

I like the fact that we have the freedom not to register. This is why I don't register, because I don't have to. It might seem a bit silly, but it's one of the few places on the net where this freedom is preserved. If I registered, it would seem to diminish that somehow.

Heres a tip, use Notepad (or the equivalent on an Apple Mac or Linux, see I'm not prejudiced!) to type your message, and then copy and paste into the chat box here.