Here's an interesting article I read. It talks about the differences between Secure Erase (ATE-SE) and block erasure methods (the typical pass over wipes I believe).
The author of the post says, "However: remember that data CAN (probably) be recovered from a drive wiped by ATA-SE. Granted, the level of expertise and equipent is high and time committed is huge ? but it CAN (probably) be done." Now from what I've read isn't Secure Erase supposed to be infallible and work similar to how TRIM does?