No you cannot delete them all.  As you correctly read 88.2 prohibits changing or deleting certain prescriptions.  For international events you should put those prescriptions that do apply on the official notice board so that everyone can read them.

Thanks John. Does a World Championship have a special dispensation for this? I have posted the full Rx's for a couple of international events I'm involved with (fortunately, as a Worlds, Appendix R is moot for that one!), and was recently pointed out to me as I prepare the SIs, the Rx to RRS 76.1 has been amended by USSailing. So we amended the NoR to get it out there ASAP.

My reading of 88.2 is that the NoR or SIs can change prescriptions, unless the MNA has applied to WS to restrict changes to its prescriptions, and that restriction has been approved.  You'll have to look as US Sailing's prescriptions to see if they change 88.2.

Carl - No, world championships do not have a special dispensation to eliminate all prescriptions.  The prescriptions that the US requires in 88.2 typically are related to US laws that we are required to follow.