Scott explained :
Can I take it that where a lamp or shade states a maximum wattage,
this is for incandescent bulbs and any LED will be okay (on the basis
that LEDs use so much less power), or is the light intensity likely to
be an issue liable to cause fading?

An LED is very susceptible to damage from its own heat build up, much
less of an issue is likely heat damage to the shade it is in. If the
shade allows good airflow and cooling of the LED, likely it will not be
a problem.