LEA or ADD instruction?

Question

When I\'m handwriting assembly, I generally choose the form

lea eax, [eax+4]

Over the form..

add eax, 4

I

Answer 1

LEA isn't faster than ADD instruction the execution speed is the same.

But LEA sometimes offer more than ADD. If we need simple and fast addition/multiplication in combination with second register than LEA can speed-up program execution. From the other side the LEA doesn't affect to the CPU flags so there is no overflow detection possibility.