hmm, I'm not sure about it being boots of the planes - there's nothing in its description indicating getting lost in time and space. instead, it horror marks you.
The dimensional rod, otoh, does say you run the risk of being lost in time and space, though I haven't ever seen this. I'm not sure why you would equip a super pretender with it; unless it was when first trying to get to Wish.
No idea how long it takes to come back, on average.
edit: no way to cure insanity, or remove curses, or reduce horror marking
The dimensional rod does cause insanity, so it sounds to me that that's what's going on, and you just haven't noticed the insanity icon before. Load up an old turn, if you have one, and check.
Re: Lost in Time and Space?
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