Spoilers ahead
I assume as many times as he got close to the city.
He didn't blast it 10 years ago because Jecht bumped into him while training in the sea, apparently far enough for Sin to not see DZ and obliterate it.
Mtbanger posted...Also I just kinda assumed that Tidus was the DZ summoning approximation of Shuyin, that is, they're actually the same person, just that Tidus is a (very) rough approximation of him that has changed over a thousand years.
The thing with this is that the people in DZ are summoned by dreams of the fayth. If they were to base a dream of theirs on Shuyin, they do so with what they know about Shuyin, which is his current self during the Machina War. Instead, Tidus is not dreamed (dreamt?) in his teens, he is born like anyone else, he's a kid and then he grows up and turns to be similar to Shuyin. For the fayth to base all of this they would have to know Shuyin's lineage for the past 1000 years to make it match Tidus's (which would mean Shuyin had a Jecht look-a-like father, etc). This is a bit of a stretch, in my opinion. For me the most reasonable thing is: he just looks like Shuyin, that's it.
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