;doc:Reduction methods: edits

Author: simonmichael

hledger/hledger.m4.md

@@ -7062,20 +7062,22 @@ $ hledger print --lots desc:sell
 
 ## Reduction methods
 
-When a disposal or transfer doesn't specify a particular lot (eg the amount is `-5 AAPL` or `-5 AAPL {}`),
-hledger selects lot(s) automatically using a reduction method. The available methods are:
-
-| Method             | Lots selected      | Disposal cost basis       |
-|--------------------|--------------------|---------------------------|
-| **FIFO** (default) | oldest first       | each lot's cost           |
-| **LIFO**           | newest first       | each lot's cost           |
-| **HIFO**           | highest cost first | each lot's cost           |
-| **AVERAGE**        | oldest first       | weighted average cost     |
-| **FIFOALL**        | oldest first       | each lot's cost           |
-| **LIFOALL**        | newest first       | each lot's cost           |
-| **HIFOALL**        | highest cost first | each lot's cost           |
-| **AVERAGEALL**     | oldest first       | global weighted avg cost  |
-| **SPECID**         | one specified lot  | specified lot's cost      |
+When a disposal or transfer doesn't specify a particular lot (eg the amount is like `-5 AAPL {}`, or just `-5 AAPL`),
+hledger selects lot(s) automatically using a reduction method.
+This is configured by giving the commodity's (or account's) `lots:` tag a value.
+The available methods are:
+
+| Method             | Lots selected      | Disposal cost basis       | Error checking
+|--------------------|--------------------|---------------------------|---------------------------------------
+| **FIFO** (default) | oldest first       | each lot's cost           | Sufficient lot(s) exist in the specified account.
+| **LIFO**           | newest first       | each lot's cost           | "
+| **HIFO**           | highest cost first | each lot's cost           | "
+| **AVERAGE**        | oldest first       | weighted average cost     | "
+| **FIFOALL**        | oldest first       | each lot's cost           | Sufficient lot(s) exist in the account, and are highest priority across all accounts.
+| **LIFOALL**        | newest first       | each lot's cost           | "
+| **HIFOALL**        | highest cost first | each lot's cost           | "
+| **AVERAGEALL**     | oldest first       | global weighted avg cost  | "
+| **SPECID**         | one specified lot  | specified lot's cost      | This lot exists in the account, and has sufficient balance.
 
 **HIFO** (highest-in-first-out) selects the lot with the highest per-unit cost first,
 which can be useful for tax optimization.
@@ -7085,7 +7087,8 @@ disposal cost basis, rather than each lot's individual cost.
 This is required in some jurisdictions (eg Canada's Adjusted Cost Base, France's PMPA, UK's S104 pools).
 Lots are still consumed in FIFO order for bookkeeping purposes.
 
-**SPECID** (specific identification) is in use if a journal entry contains explicit lot selectors like `{2026-01-15, $50}` or `{$50}`,
+**SPECID** (specific identification) is what you're using if the journal entry contains 
+explicit lot selectors like `{2026-01-15, $50}` or `{$50}`,
 or an explicit lot subaccount like `assets:broker:{2026-01-15, $50}`.
 
 ### All-accounts reduction