it would be foolish to assert that it [machine matzah] is better than hand-made matzah
No, it would be foolish to say that it’s impossible to bake hand matzah that’s not chametz, but not foolish to say that today’s machine matzah is superior to the hand matzah available today.
Shlishi,
18 minute (machine) matzah means the machines are stopped and cleaned every 18 minutes, which is not relevant to when the shmirah started on the wheat.