One problem for Transformational grammar solutions is the idea of feature percolation. Say you have a sentence like this:
1. You gave money to him.
Now let’s make it into a question.
Now let’s try moving the wh-question word.
2. Who did you give money to?
But this is also a good sentence:
3. To whom did you give money?
Actually, these feature percolation facts are a huge problem for the Minimalist Program. If features can be matched (or unified), why do we need movement? Just having copying is a better Minimalist approach.
Make up your own mind — or just keep an open mind
If the Chomskyans are right, we are born with communicative ability that is really fundamentally different from other animals. We are born with grammatical rules wired into our brains! Maybe this ability has a perfect design.
If the Unificational Grammar people are right, then everything boils down to a copying/matching mechanism. Maybe we are not so different from animals after all. What do you think?
Anyway, take a look at the PowerPoint slides here.