Well, for me it wasn't to do with respect for the ancients - they're dead & don't care - it was more to do with not wanting to do ANY damage, no matter how invisible or infinitesimally small.

If a person or people went traipsing around through the houses every night, or every other night, or once a week, or once a month, invisible infinitesimally small damage would become less invisible & less infinitesimal.

I think our logic was as Rhiannon said - we were only doing exactly what we would have been doing if we'd entered during opening hours, so definitely wouldn't be doing ANY damage that we wouldn't've done if we'd gone in when it was open.

love

Moth