In my experience working with developers, we are frequently making updates on the fly, refreshing our browsers and not seeing the changes propagate on the screen. We'll go back over and over again and clear the cache and destroy the web data hoping for the changes to finally show.
But obviously I don't want to destroy all of my cache / web data. It'd be awesome to just be able to dump the cache to the specific url or domain that we're working in. All in a quick keystroke. It could be implemented through the already set options on safari or chrome for clearing the cache, but make it specific to the current page.
I'd love to see Apple implement a continuous scroll position between mobile safari, and desktop safari. It'd be great for the two browsers to be even more so in sync. I often get halfway through articles only to walk away from my desk and realize I didn't bookmark it the article, or haven't added it to pocket.