What's the advantage over having the user solve a captcha on the site itself?
Well, it's said that sometimes captcha can be failed to prevent the bot (RUMOURS).
So I think make it 2 captcha while gain more profit from the ads.
You can put 2 captchas on the main site. How does a url shortener stop bots?
Well cause some shortener url have their own way to stop bots, like AdFly, and I can earn more from them.
I think is shortened url bad idea. Faucet user like it when it is easier to claim earnings. additional clicks, captcha, "anti-bot" clicks did not work well.
also as far as I know some advertisements network do not allow to use shortened url
You're right. My website get a 1000% more traffic rate* after I switched http://bitrevenues.com/ from members-only lottery game to an 'anonymous' lottery game - there is no need to register, all users need is to fill in their Bitcoin address and captcha and then click enter.
* or so I though after looking at the analytic.
