LotR2-TTT-Seq07

[Tuor of Gondolin]

just why did Gandalf let Merry and Pippin in the keeping of Treebeard? In the books I think that the White Wizard is aware of this, but I don’t think that he and Treebeard sat down and discussed what to do with the hobbits.

My impression in the book is that Gandalf did not actually
meet up with Treebeard and the hobbits until he was rounding
up forces to help relieve the siege of Helm's deep.

And yes, it's about time for PJ to go off the wall by
making the white wizard Gandalf the Enforcer (and
he similarly decided (as Andy Serkis said) to change
Gollum's motivation to indicate that he never (unlike in
the book) was really tempted to, as it were, leave the
dark side.