If, Unless Patterns

From the book, I learned that there are 5 If ... Then patterns.

1. If present, then present

2. If present, then can/may

3. If present, then future

4. If hypothetical subjunctive, then conditional

If pete ATE pizza tomorrow, THEN he WOULD BECOME ill.

5. If past perfect, THEN conditional perfect

If Pete had eater pizza yesterday, then he would have become ill.

The book says Anything outside these patterns in if.. then construction is ALMOST ALWAYS incorrect.

Do you know any similar kind of patters for unless or connecting words?

Also, from the book, I read,

A patient accusing a doctor of malpractice WILL find it difficult to prove damage UNLESS there WILL be another doctor to testify - It is wrong. Because, in UNLESS pattern, two WILL in 2 clauses is wrong.