Are unaligned reads really expensive?

Are unaligned reads really expensive?

  Since college days, I had come to understand that processor is very good at reading data which is aligned at word boundaries. Any unaligned memory read is considered to be slower. But when I recently saw such a read operation in a piece of code, I was trying to optimize, I was surprised to see no change in the performance after removing the unaligned read operation. After Googling on the same, found the following article

http://lemire.me/blog/archives/2012/05/31/data-alignment-for-speed-myth-or-reality/

  It turns out that modern Intel processors handle unaligned reads, as efficiently as, aligned memory reads.

Note: This is applicable to Intel processors only.