Inconsistent behaviour in _inherits

If one object _inherits from another (like product.product from product.template) and both objects have a column with the same name, the value of the father is shown in the view, however when saving the child object, the child's table is written.

Example:

Try to move 'weight' field from product.template to product.product. You can define a 'weight' column for product.product. When you open the product form, the displayed 'weight' will be the one retrieved from the product_template table, but if you change the value and save it, the value will be saved on the product_product table.

Expected behaviour: When the same column exists in both, parent and child, the child's value should be used.