In 1.0 my capsule would explode on the most shallow re-entry coming back from the Mun, without a heatshield. In 1.0.2, I came back from Duna with an entire craft, at 6.000 m/s on virtually the same trajectory, and the ship was fine. Also I have noticed that on a trajectory where your ablator is gonna fully burn up, a craft or capsule without a heatshield will be perfectly fine regardless. So yeah, the changes between the two versions are pretty radical.