The possibilites are endless...
DVD makes watching tickling a great idea.
Take for example the hot-tie.
Ok, it frees up the tickler to get to the feet and usually produces a great response from the ticklee.
Here is the problem for the tickling producer.
Which shot should he/she get, the facial reaction, or the tickling of the feet?
Well with DVD, the producer, could use TWO cameras to shoot the scene one trained on the facial expressions and on the feet or wherever the tickling is occuring, then using the multiangle feature native to DVD.
The producer could allow the viewer to pick which angle to watch.
Maybe angle 1 is facial, angle 2 would be feet, and angle 3 could be angle 1 and 2 next to each other!!! So you can see the torment of the soles and the facail reaction at the same time.(Very important to some with a tickling fetish.)
That is just one example. You could do that with any scene you like.
Yeah it would require more effort and another camera and someone to make the DVD(now with PC/MAC you can produce your own).
But I for one would get a DVD that mentioned this as a feature.