In areas with a TT supply it's been common practice to slap everything on a whole-house RCD for ages and the most common nuisance tripping issue was lightning (transients) by far. These days OVE requires at least two RCDs for domestic buildings but I still see new homes with one RCD for everything. Our flat was last renovated quite some time ago so we only have one RCD and TBH I can't remember the last time it tripped.
Was the power strip by any chance a surge protector strip? These usually have varistors wired from line and neutral to earth and when they blow due to a surge they trip the RCD.
Neutral earth faults in fixed wiring are where it gets interesting...
