lightswitches and checkboxes added to existing entries do not respect the field's default value

[olets]

Description

If you add a lightswitch or checkbox field, it gets the "off"/"unchecked" value on existing entries regardless of the field's default value (entries created after creating the field will be properly use its default value).

Additional info

This is a known effect. See

• http://craftcms.stackexchange.com/questions/11269/can-i-add-an-enabled-by-default-lightswitch-field-to-existing-entries
• http://craftcms.stackexchange.com/questions/19113/can-the-lightswitch-field-have-a-default-on-setting

Note that, in keeping with the asker's comment on the selected answer for that first SO link, I'm getting 0 for the lightswitch, not null.

I'm on v2.6.2959