zadokk
I do not think so. The rule says "different played tactics", Sun Tzu upgrades a tactic, but it's not a new tactic, it's the same card, like any other upgrade. When Great Wall upgrades an infantryman it is not a new unit, nor is Fleming's upgraded opera house a new building. I think the maximum should be 17 tactics.
It also says "played", when you play it from your hand the card is no different even if Sun Tzu's benefit is applied to it later.
What do you think?