I agree with this and when the opportunity arises to cast a vote on the availability of presentation modes, I will vote for (optional) full presentations.
Of course the devs are smart enough to do marketing research beforehand and their decisions must have been based on the (predicted) usage of Vita users. But there are use cases that might have gone out of their radar... in which case we just remind them that we want certain things......
And from what it looks like from the response here that there aren't many prospective the-Show buyers who would not want full presentation on Vita.