As I was behind I decided not to do the practice foundations but to do foundations that I could use in the "proper" blocks. The 16 patch is for Indiana Puzzle, using 4 four-patches which were cut at 4-1/2" and not 8" as the pratice foundation was.
For each of my foundation blocks I have taken the measurements from a "proper" block, so then (if it worked out O.K.) I have it ready to use.
I hope this explains the difference. Knowing that I am a slow worker and being late getting started, I was trying to save a bit of time with the foundations.
Sorry if I created any confusion.