Lead arm question

[ncsouthpaw]

I am trying very hard to figure out all that I am reading/learning on this site.

One issue I am confused about is the proper degree of bend in the lead arm. From watching many thumbnails it seems many high level players keep almost the same degree of bend from first motion to impact. Manny, Ortiz and Bonds seem to keep shape throughout but Lee and Pujols sometimes seem to almost straighten out their lead arms for a split second before having the bend back at impact.

Is this just an optical illusion, am I missing something or is there another issue/explanation involved?

[FiveFrameSwing]

Maintain the box.

[Mark H]

It's not the degree of bend, it's maintaining connection. Can the arm and bat be a segmented whip toward the end? Sure, but through most of the swing, maintain the box.