Merge pull request PSLmodels#2836 from martinholmer/tcja-doc

Update tcja_after_2025.md documentation

docs/usage/tcja_after_2025.md

@@ -86,23 +86,12 @@ To analyze your reform relative to a reform that extends all TCJA
 temporary provisions beyond 2025, you would execute this command:
 
 ```
-tc z.csv 2026 --exact --tables --baseline ext.json --reform x.json
+tc z.csv 2026 --exact --tables --baseline ext.json --reform ext.json+x.json
 ```
 
-The tables would be in the `z-26-ext-x-#-tab.text` output file
+The tables would be in the `z-26-ext-ext+x-#-tab.text` output file
 generated by this `tc` run.
 
-Also, remember that you can simulate a _compound reform_ using the
-following syntax:
-
-```
-tc z.csv 2026 --exact --tables --baseline ext.json --reform x.json+y.json
-```
-
-where `y.json` contains a reform with additional provisions not
-included in your `x.json` reform file.  The resulting table output
-would be in a file named `z-26-ext-x+y-#-tab.text`.
-
 And finally, you might consider creating a reform file called
 `end.json` that contains just the two characters `{}`.  This is a null
 reform, which is equivalent to current-law policy, that could be used