diff --git a/SMPDataFlowAnalysis.cpp b/SMPDataFlowAnalysis.cpp
index b70bfd8c46b14ab9876718db51744cf0e76eedb6..59ee70206eb621b30d9e5509bc85b804b85bd1ea 100644
--- a/SMPDataFlowAnalysis.cpp
+++ b/SMPDataFlowAnalysis.cpp
@@ -1940,7 +1940,9 @@ void InitTypeCategory(void) {
 	//   If new instructions are added to this category that are not single
 	//   operand and do require some updating, the category should be split.
 	// Category 5 instructions have a result type identical to the 1st source operand
-	//  type whenever the 2nd source operand is an operand of type 'n'.
+	//  type whenever the 2nd source operand is an operand of type 'n' & vice versa.
+	//  Examples are add, sub, adc, and sbb. There are subtle exceptions
+	//  handled in the SMPInstr::EmitTypeAnnotations() method.
 	// Category 6 instructions always have a result type of 'p' (pointer).
 	// Category 7 instructions are category 2 instructions with two destinations,
 	//  such as multiply and divide instructions that affect EDX:EAX. There are
@@ -1952,10 +1954,9 @@ void InitTypeCategory(void) {
     // Category 9 instructions are floating point instructions that either
     //  have a memory destination (treat as category 13) or a FP reg destination
     //  (treat as category 1, as FP regs are always 'n' and ignored in our system).
-	// Category 10 instructions have 'n' results if the sources are all 'n'; they
-	//  have 'p' results if the sources are all 'p'; and we cannot infer the type
-	//  of the result if the sources are of mixed types. Bitwise OR and AND are
-	//  examples.
+	// Category 10 instructions have 'n' results if the sources are all 'n';
+	//  we cannot infer the type of the result if the sources are of mixed types.
+	//  Bitwise OR and AND and LEA (load effective address) are examples.
 	// Category 11 instructions need to have their types and locations on the stack
 	//  frame tracked, e.g. push and pop instructions. No direct type inference.
 	// Category 12 instructions are similar to category 10, except that we do not
@@ -2026,13 +2027,13 @@ SMPTypeCategory[NN_imul] = 7;                // Signed Multiply
 SMPTypeCategory[NN_in] = 0;                  // Input from Port                         **
 SMPTypeCategory[NN_inc] = 4;                 // Increment by 1
 SMPTypeCategory[NN_ins] = 2;                 // Input Byte(s) from Port to String       **
-SMPTypeCategory[NN_int] = 1;                 // Call to Interrupt Procedure
-SMPTypeCategory[NN_into] = 1;                // Call to Interrupt Procedure if Overflow Flag = 1
-SMPTypeCategory[NN_int3] = 1;                // Trap to Debugger
-SMPTypeCategory[NN_iretw] = 1;               // Interrupt Return
-SMPTypeCategory[NN_iret] = 1;                // Interrupt Return
-SMPTypeCategory[NN_iretd] = 1;               // Interrupt Return (use32)
-SMPTypeCategory[NN_iretq] = 1;               // Interrupt Return (use64)
+SMPTypeCategory[NN_int] = 0;                 // Call to Interrupt Procedure
+SMPTypeCategory[NN_into] = 0;                // Call to Interrupt Procedure if Overflow Flag = 1
+SMPTypeCategory[NN_int3] = 0;                // Trap to Debugger
+SMPTypeCategory[NN_iretw] = 0;               // Interrupt Return
+SMPTypeCategory[NN_iret] = 0;                // Interrupt Return
+SMPTypeCategory[NN_iretd] = 0;               // Interrupt Return (use32)
+SMPTypeCategory[NN_iretq] = 0;               // Interrupt Return (use64)
 SMPTypeCategory[NN_ja] = 1;                  // Jump if Above (CF=0 & ZF=0)
 SMPTypeCategory[NN_jae] = 1;                 // Jump if Above or Equal (CF=0)
 SMPTypeCategory[NN_jb] = 1;                  // Jump if Below (CF=1)
@@ -2072,7 +2073,7 @@ SMPTypeCategory[NN_jmpni] = 1;               // Indirect Near Jump
 SMPTypeCategory[NN_jmpshort] = 1;            // Jump Short (not used)
 SMPTypeCategory[NN_lahf] = 2;                // Load Flags into AH Register
 SMPTypeCategory[NN_lar] = 2;                 // Load Access Rights Byte
-SMPTypeCategory[NN_lea] = 0;                 // Load Effective Address           **
+SMPTypeCategory[NN_lea] = 0;                // Load Effective Address           **
 SMPTypeCategory[NN_leavew] = 0;              // High Level Procedure Exit        **
 SMPTypeCategory[NN_leave] = 0;               // High Level Procedure Exit        **
 SMPTypeCategory[NN_leaved] = 0;              // High Level Procedure Exit        **