Whatever investing strategy you settle on, be it lump sum or dollar cost averaging, you´re going to execute it once, not 4000 times or some such.  I haven´t read the posts, just looked at the graphic comparing large samples.  No mention of variance.  Okay, I don´t wanna get in a scrum with people, this seems like a contentious issue, so please don´t adopt my in support of your argument or lambaste me as helping the other side.  I´m going for a walk now.