depends on who you listen too i guess apparently 1 amp is nothing to worry about, but then don''t quote me (that's if your still around to do so)
what concerned me was the false sense of security you can be led into by seeing an RCD but not realising that really with a 100mA model your as safe as without it
well the new distribution box with the 100mA RCD in it was not put in in 1987, I think the original fuse box that is just sitting there unconnected was what was originally there, its just all been rewired through the new box, I think after a quick glance round that the only other modifications "the bodger" made was to put dimmer switches in (on energy saving bulbs - yea clever)