In edit fields > new and update, what is that for!?

hello

please see attached image, anybody knows what are those for ? I tried to play with them, though it will not be available in new or in update but I saw they have no effect? why are they? is anybody using them?

newupdate.png

If the field should be visible in insert and/or update mode.

http://www.scriptcase.net/docs/en_us/v8/manual_mp.htm#form-applications/form/edit-fields

jsb

looks genuine, but i remember 've tried it earlier it wasn’t showing any effect, okay will try it again

appreciated your time jsb

cheers