Seriously, you are claiming that network latency and a delayed response to click events is a GOOD thing because it lets you fix mistakes that you made? Sorry, that is not how you design a product/feature.
The problem you are mentioning has also been solved by Google. In Ice Cream Sandwich when you click on a link that is close together with others, it will magnify the area to make it very clear which link you want to click. This is a solution to your mis-clicks - not a latency delay on every click so that you can fix it if you clicked wrong...
In the absence of zoom-on-ambiguous, why is it so bad? I certainly have trouble accurately clicking links on a phone, so having no click correction is certainly worse than artificial latency.
Don't confirmation dialogue boxes and password confirmation fields fall into the same category? They assume imperfect user input, and their mechanisms for avoiding errors slow the user down.
What's right for web sites (300ms delay) need not be what's right for web apps (0ms delay). I think it's a smart default, and devs making usability tradeoffs can decide when to remove it.
The problem you are mentioning has also been solved by Google. In Ice Cream Sandwich when you click on a link that is close together with others, it will magnify the area to make it very clear which link you want to click. This is a solution to your mis-clicks - not a latency delay on every click so that you can fix it if you clicked wrong...