End Phase MST!?

Since I've been in the competitive scene, end phase MST has been a huge factor in disrupting hidden spells/traps. As the game progressed I started leaning against setting Typhoon as I felt the need not to.The whole idea popped in my head after I heard Frazier Smith talking about the mindset he has towards the game. It can be found [Here].
He talks about his need not to set MST and also gives an interesting example in the form of Thunder King Rai-Oh!. He says, "Here's what I realised about the game right now. Thunder King is like the best monster to summon first turn, obviously. With that being said, he's such a strong presence offensively and defensively that you can set MST when you summon him first turn" he then says, "and it just keeps the pressure on, like if I end phase MST when I have Thunder King on the field it's like, awh, man. You had a D-Prison? Or something that you wanted to use? I got you now."

With the arrival of the water deck (Mermail Atlanteans) and their trap Abyss-Sphere, can we even waste our Typhoons? Yes, you can run three copies but that just means you only have three chances to make some use of it. Certain match-ups, (like Dark Worlds) I can see myself using Typhoon in the end phase even if it's blind, just so I can hit those pesky traps such as Reckless Greed.

Along the idea of traps:
What if you're facing Trapless-Agents? Chaos Dragons? Decks that run
little to no traps?

End Phase MST would achieve nothing in these matches, they're dead. I'm sure you can bluff setting it but you're allowing them to snowball while you watch that Gorz you drew a turn later.

The questions I have for you now are, when do you set your Typhoons? Do you even set them? How many copies do you run? Do you feel the need at times to set MST?