If airlines, and BA is not the only one, forbid raw data flying, and discourage manual flying entirely, why is a raw data ILS still in the type rating LST? The XAA's deem it a necessary skill. If so then surely they should also encourage its retention. You do one with an LST and then never again in any mandatory test. You are forbidden, by your employer, under approval of the same XAA to retain this required skill. Why bother with the test in the first place if the same XAA does not enforce it throughout your career? Why not, at least, include it in LPC's instead of assuming some airlines will include it in their 'tick in the boxes' 3 yearly RST of flight controls? By doing that the XAA's would take a proactive role in reducing the dilution of piloting skills, if only by a smidgen.