Better serving of CAPTCHAs to commenters

[trixieleitz]

Title
Better serving of CAPTCHAs to commenters

Short, concise description of the idea
The comment form should detect when the commenter has chosen options that would result in them being asked to complete a CAPTCHA, and use Ajax or some other Code Magic (tm) to load a CAPTCHA immediately, without requiring the whole page to be reloaded.

Full description of the idea
Let's say I'm logged in to my account, but I want to comment anonymously on a particular entry. The owner of that journal has set it so that all anonymous commenters need to complete a CAPTCHA. Cool. Right now, I will select the anonymous option from the menu, type up my comment, and submit it, which results in a reload and an error message. Not so cool. Then I submit my CAPTCHA response, and, assuming I typed it right, the comment goes through on the next reload. It would save me some time if the comment form could magically detect that I had selected an option that would require a CAPTCHA, and load that little bit of the page immediately. The CAPTCHA would magically appear, I would fill in my response, and just click the submit button once per comment.
An ordered list of benefits

• One fewer page reload to post anonymously while logged in
• One fewer page reload to post from a non-friended account while logged in to a friended account
• I could bank the time saved and use it to think about problems/issues with this suggestion.

An ordered list of problems/issues involved

• Needs to have a graceful fallback if the user's browser doesn't support the code used (eg JavaScript). I suggest the current system, clunky as it is.
• Needs to be able to cope with the reverse situation (taking away the CAPTCHA if the commenter selects an option that doesn't require it).
• One fewer opportunity to think better of that comment and close the tab before posting it.