diff --git a/todo.md b/todo.md
index 4aaedc0..1281de7 100644
--- a/todo.md
+++ b/todo.md
@@ -2,14 +2,13 @@ things to try:
 
 * patch the entire expanded-ram imul8xe on top of imul8 to avoid the 3-cycle thunk penalty :D
 
-* optimize out a store/load with mul8_add16 and mul8_add24
-
 * try 3.13 fixed point instead of 4.12 for more precision
   * can we get away without the extra bit?
 
 * y-axis mirror optimization
 
 * 'wide pixels' 2x and 4x for a fuller initial image in the tiered rendering
+  * maybe redo tiering to just 4x4, 2x2, 1x1?
 
 * extract viewport for display & re-input via keyboard