The borrower now has bank notes or a book of checks. If this is your concept of endogenous money, then you don't understand endogenous money. The effect on the bank's capability to make loans in either example is exactly the same. On day one in the very beginning, the reserves the bank has against its deposits is exactly 100 percent. Once the bank makes a loan, however, its reserves become less than 100 percent, which is the theoretical concept of fractional reserves.
Banking is a variation of the concept of insurance, the shared pooling of risks.
It helps the wheel of commerce to turn. This is simply wrong. What determines a bank's lending limits is its capital ratio, not its reserve ratio. If you understand the concept of an endogeneity, you will realize that the reserve ratio requirement is essentially meaningless. You're confusing theories of law with theories of economics.