[kosma]

The nature of surges is not simple like that - a lightning strike can easily blow MOVs and inrush limiting resistors in multiple devices. I come from a rural area and coming to someone's house with a bag of fresh MOVs and resistors is not an uncommon thing after a big storm.

[4gotunameagain]

I believe that it highly depends on the type of the surge protector, their ratings and the cable network involved. I do not think that it would cause issues in two surge protectors from power outlets connected in series, and depending on their rating and switching characteristics maybe both could trigger, I agree.

[numpad0]

I believe the question is if it's safe at all to do so rather than whether the protection works or not, though I'd have to be all ears about interactions between multiple parallel surge arrestors.