What is the best approach for a standard THS?  Take something strong and move inside out of the gate?  Or use a milder cover/surface/layout and play more up the boards?

I've seen both approaches work well...sometimes even on the same pair.

Thoughts?

For me it depends on who I'm bowling with and what they are throwing.

for my game, i like to think of myself as a right hand minded lefty. im rev dominant and with the ths i see using a weaker ball like a Vibe puts me into 13-14 at the arrows and 5 downlane on the fresh. the good news is i dont really have to move much all night. i could use more of a benchmark type ball like a disorder or hyroad solid or hysteria etc. but that would put me inside 3rd arrow out to 5-6 on the fresh and id rather not be that deep from the start because ill start getting traffic in the heads from the righties

I don't think that there is a right or wrong answer to this. The approach varies by bowler, bowling center, pattern being used, lane surface, who you are bowling against, etc. As such, as others have said, it's best to just be observant and see what the bowlers around you are doing. Generally speaking, if it's truly a THS, you don't have to put too much thought into it. I would just avoid the extremes. Don't come out throwing a 360-grit Crux or a 4000 highly-polished Tropical Breeze Pearl. In terms of line, I wouldn't come out trying to play 6th arrow, and I'd avoid trying to use the 1-board too. Just keep it simple.

For me, I generally start my THS league standing around 27 (I drift about 6 right) with a medium-strength ball (Zero Gravity, IQ Fusion, etc.) and play a gentle belly through the middle of the lane. This usually provides me with a little bit of hold if I'm in and decent recovery unless I throw it out the window to the right.

Now, if I'm bowling with a bunch of guys who like to go straight and burn up the track, I often move right, ball down and play there with them because staying left of them usually forces me way too deep in order to get the ball to push through the area that they're burning up. When playing those straighter lines, I prefer a ball that reads earlier and stays smooth; otherwise, the ball dives too hard at the break point, and I am in for 9-pins and/or designer splits.

On the flip side, if I'm bowling with a bunch of hi-rev guys, I generally try to jump in with them. Even though I don't rip the cover off of the ball the way some of them do, I can use the friction they're creating to give me great recovery out and more hold than they get in. For this, a hybrid like the IQ Tour Fusion works really well in most cases, though sometimes I can go up to something like the Zero Gravity or possibly ball down to the Punch Out.

As Gene stated, there will be no right or wrong answer, just what works best for you.  Some houses have higher friction lane surfaces and so the weaker balls can be your friend.  The opposite can be true for fresh shots with some volume.

I'd suggest watching closely your ball reaction and carry as the night progresses.  Most of us can get lined up to strike in game one, but what happens after that?  Even if you're able to start with a stronger ball, you may need a weaker one as the lanes transition to help with carry. 

Don't be afraid to experiment a little.  Even if you choose the wrong direction you're likely to still make spares at worst, which is probably no worse than you already are or the question wouldn't exist, with the possible upside of finishing very strong with the weaker ball.  Good luck.

I never bring a strong ball to league play. I am rev dominant with slow speed in the 14mph range. Bringing a strong ball is like overkill, and I probably will only use it for half a game.

It's usually a weak ball drilled strong on the fresh, and then weaker, weaker still. I like to start out right and then move left.(typical) but my best play is in the middle of the lane with a small belly.

Personally, I have done both. Whatever works for you the best and whatever you are most comfortable with.

I like to use as weak of a ball as possible, with a little surface. At one house, that means starting out with my Darkness or Network, keeping it in the ample puddle until about 38 feet. More direct I go there, the better my carry is and the easier it is to keep up with the transition, which usually kills me.

At another house in the area, which has much more friction, I will start out with a King Cobra or Sure Thing, and either ball down to a Hook, or move in and use a War Eagle or Dirty Look.