Hey ProUnion,
Although there are no specific references not allowing the "Taping" of Anti-short(Red-Heads) bushings in BX cable,There are Specific requirements for an "approved" installation.
NEC 2002,110-3a(1) "Suitability of equiptment use may be Identified by a description marked on or provided with a product to identify the suitability of the product for a specific purpose, environment, or application." Keyword here being "specific".
NEC 2002,110-3b "Installation and Use - Listed or Labeled equiptment shall be used or installed in accordance with any instructions included in the listing or labeling." Keyword here being "shall".
These rules clearly and certainly says that any and every product listed in the UL Electrical Construction Materials Directory (Green Book) must be used EXACTLY as described in in the application data given with the listing in the book.
If Taping the Red-Head is not listed then you cant do it.
Another consideration is that according to NEC 2002, 250-33 states that "All metal raceways and enclosures containing conductors shall be grounded." Taping the Red-Head could interfere with the bond that the BX cable clamp and lock-nut provides.
I hope I have been of some help. Good luck.
JTapia