Read it. Ask me questions. Then we can go back and talk implementation.
Reading it (slowly, between distractions). I found these interesting so far...
3.1 The execution speed component of system performance includes not only how many instructions can be performed per second on straight line code, but also speed in handling interrupts, context switches, and performance degradation due to factors such as conditional branches and procedure calls.
3.3.2.2 Short, frequent procedure calls
The main characteristic of Forth programs that separates Forth from most other languages is the high frequency of subroutine calls. Good Forth programming style encourages incremental program development and testing with small subroutines. Subroutines often only consist of 5 or 10 instructions. A static frequency of approximately 50% of the instructions being subroutine calls is considered normal.
In theory there is no difference between theory and practice, but in practice there is.