No, thought is not always random, but you asked how to spot rings and regrow trees and the best way I've found so far is to do the spotting/navigation with the mind. Sounds kooky, I know. I don't dispute that. Deal is, I don't think very many people can do it, therefore they would need assistance from a machine and machine would have to process the input (or magnify) from the mind.
With out this psychological anchor, time travel itself becomes random and you get "lost in time".
I think the technology needed/missing would be a EEG or fMRI type machine that can process a linear stream of thought. It does not have to have the processing capability of a human brain, just enough to hold a thought, so to speak.