You guys seem to be underestimating the difficulty in pin pointing an existence within the timestream. Yuki knows exactly what the STTGL is and its abilities even before the match starts while the STTGL knows nothing. Yeah it can punch holes through the universe or whatever, but unless 1. Yuki's "Brain" exists within one of these AND 2. The STTGL has some sort of outside knowledge of where she is (and a way to actually pin point this). I don't see it getting off a hit.
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Chrono1219