added comments

src/main/java/baritone/bot/pathing/movement/movements/MovementAscend.java

@@ -98,6 +98,10 @@ public class MovementAscend extends Movement {
                 // so don't do it
                 return COST_INF;
             }
+            // you may think we only need to check srcUp2, not srcUp
+            // however, in the scenario where glitchy world gen where unsupported sand / gravel generates
+            // it's possible srcUp is AIR from the start, and srcUp2 is falling
+            // and in that scenario, when we arrive and break srcUp2, that lets srcUp3 fall on us and suffocate us
         }
         // TODO maybe change behavior if src.down() is soul sand?
         double walk = WALK_ONE_BLOCK_COST;

src/main/java/baritone/bot/pathing/movement/movements/MovementPillar.java

@@ -65,6 +65,9 @@ public class MovementPillar extends Movement {
                 BlockPos chkPos = src.up(3);
                 IBlockState check = BlockStateInterface.get(chkPos);
                 if (!MovementHelper.canWalkOn(chkPos, check) || MovementHelper.canWalkThrough(chkPos, check) || check.getBlock() instanceof BlockFalling) {//if the block above where we want to break is not a full block, don't do it
+                    // TODO why does canWalkThrough mean this action is COST_INF?
+                    // BlockFalling makes sense, and !canWalkOn deals with weird cases like if it were lava
+                    // but I don't understand why canWalkThrough makes it impossible
                     return COST_INF;
                 }
             }