It came with the last versions before Bob Zale passed away, I always hated the line by line escapes and the block escapes solve that problem. The FASTPROC notation is effectively identical to MASM's no stack frame notation so I can swap code between 32 bit MASM and PB very easily, minor differences in the HEX notation, PB uses &H11223344 where MASM uses 11223344h but its easy enough to translate.
I have 20 years of 32 bit assembler written in PB and much of it ports easily to either 32 or 64 bit code. In 64 bit it is little more than changing register sizes so it means I have not wasted years of code.