Markoz wrote on Sep 14^th, 2015 at 7:06am:

The default cs727base.PLN is required for the INS to initialise when it first loads into FSX/FSX-SE/P3D. There is no need to remove it, or disable it, because once you create/load another flight plan, the default flight is replaced in the INS by it. ;)

Yes but if you use CIVA INS then its useless.
Also I use ASN for weather which autoloads (ok there is option to disable it) the FSX flight plan.