With the above framework clearly defined, it's now easy to see how Frax v1 is the simplest form of an AMO. It is essentially the base case of any possible AMO. In v1, decollateralization allows for expansion of the money supply and excess collateral to flow to burning FXS. Recollateralization mints FXS to increase the collateral ratio and lower liabilities (redemptions of FRAX).
The base layer fractional-algorithmic mechanism is always running just like before. If FRAX price is above the peg, the CR is lowered, FRAX supply expands like usual, and AMO controllers keep running. If the CR is lowered to the point that the peg slips, the AMOs have predefined recollateralize operations which increases the CR. The system recollateralizes just like before as protocol liabilities (stablecoins) are redeemed and the CR goes up to return to the peg. This allows all AMOs to operate with input from market forces and preserve the full design specs of the v1 base case.