It will work just fine. Take away the freebies and they will self deport.
Now that's a more realistic and accomplishable plan. However, it's not the red meat that Trump is selling.
The “self-deport” strategy seems the simplest, and least messy — especially if you were to also prohibit anyone from employing illegal immigrants. However, what would the courts do? Could the courts, in effect, order the continuation of welfare payments, etc.?