How does blocking increase compression?

Previously we have to store dictionary term pointers in a table:

FreqPostings ptrTerm ptr

Given a string of 3.2MB, we have 3.2M positions, so term pointers are 3bytes each.

If we do blocking, now we only store every k block term pointers.

Then we encode relative pointer offsets in the string itself.

Since words are not very long, we can encode these pointers as 1 byte.

This allows us to save 9 bytes on 3 pointers,