Q:

The following property is set to true by default in web.config

<setting name="Publishing.AutoScheduleSmartPublish" value="true" />

Does this mean that every time the incremental publishing is performed for the site, the smart is triggered instead?

A:

No, not every time. This setting automatically schedules a smart publish when proxy definitions etc. change. The items, which trigger smart publishing are defined in the <smartPublishTriggers> section of web.config. If you set the Publishing.AutoScheduleSmartPublish setting to false, users will have to manually publish all items which change due to changes in templates or proxy item definitions. This is why this setting is set to true by default.