Params de-listing documentation

contracts/params/README.md

@@ -14,3 +14,21 @@ This contract holds the following values for all the assets in Mars Protocol:
 
 Note: Credit Manager Vaults only utilize max loan to value, liquidation threshold, and deposit cap parameters, while Red Bank Markets utilize all of the above parameters.
 
+## High Levered Strategies (HLS)
+
+An HLS is a position where the borrowed asset is highly correlated to the collateral asset (e.g. atom debt -> stAtom collateral). 
+This has a low risk of liquidation. For this reason, Credit Manager grants higher MaxLTV & LiqThreshold parameters,
+granting higher leverage. An asset's HLS parameters are stored in this contract and are applied to credit accounts 
+of the HLS type during a health check.
+
+### De-listing an HLS asset
+
+There are a few scenarios depending on what denom is being de-listed. Always communicate each step to the users!
+- **De-listing a collateral denom**: 
+  - Set the MaxLTV of the denom to zero. 
+  - Gradually reduce the HLS Liquidation Threshold to zero.
+  - _Do not_ set HLS parameters to None or remove it from correlations list for debt denom. This would result in freezing the HLS accounts that have that collateral.
+- **De-listing a debt denom**:
+  - Set the MaxLTV of all denoms in the debt denom's correlations list to zero. 
+  - Gradually reduce the HLS Liquidation Threshold to zero.
+  - _Do not_ set HLS parameters to None. This would result in freezing the HLS accounts that have that debt denom.