I have done something similar to your video. However I am just using Veency on the iphone and jolly'sfastVNC on my mini. It eliminates the need for screensplitr and the need to open a web browser. All you have to do is be on the same network. I have an applescript to create a adhoc network and use it in conjunction with a program called on wake. This way every time the mini starts up or wakes from sleep I already have an adhoc network created.
The next step was writing an applescript to make the connection with jolly'sfastvnc. I simply run the applescript as an app and it makes the connection, minimizes unused windows of jolly's and then I have one small window on my screen showing my iphone screen. Then I can just control the iphone from the touchscreen. One thing you are going to want to have is sbsettings or bossprefs to toggle autolock, because if the iphone goes to sleep the connection is lost.
On a side note, another useful application is snatch for the iphone. It gives you a trackpad and keyboard you can use to control the mini. Also, I've found that screensplitrs video quality is much better if tvout is installed as well. I don't use tvout but for some reason screensplitr is better with it.