So today I was playing around with Motion tags on boats. At a certain moment, I decided to apply a Motion tag with a 'y' value. To my surprise, the boat behaved like a <1.9 boat and broke into planks and sticks upon coming back down.

Expected behavior:
The boat 'floats' down and simply lands on the ground without breaking.

Actual behavior:
The boat falls down and breaks into planks and sticks.

Steps to reproduce:
1. Get a boat (crafting, creative inventory or /summon Boat)
2. Run following command through either chat or command block: /entitydata @e[type=Boat]

Notes:

• When dropping a boat from a pillar of the same size as the jump or teleporting a boat to about the same height, the boat does not break.
• I did not research this in versions other than 1.10.2 yet.