I picked up a pre-seasoned Tri-Tip at Costco, smoked it for ~4 hours at 150° to an IT of 126°. Vacuum packed, sous vide for 26 hours at 133° and refrigerated. I've not had very good luck pan searing a roast, so I plan to bring it up to room temperature and sear in a 500° oven, keeping IT below 133°. After searing I'll cool, partially freeze and thin slice cross grain. Long sous vide time is also an experiment. It's too hot here to fire up the gasser.

Looks good! Keep us informed.

20 minutes at 500°, IT = 125°

the right side probably has a different direction of the grain

That does look really good.

Looks like a good sized tri-tip!

Tri tips are pretty easy to cook. You can cook them in less than two hours and they will come out really good. They are the most common meat that I cook.

I am interested in how much better your tri tip turns out since you have put a lot more time and effort into it.

I like the idea of experimentation in the kitchen. I hope it works out for you, but even if it does not, you will probably learn a lot from the effort.

The method I have not tried in traditional Santa Maria style since I don't have a Santa Maria grill.

 Do you know what the seasoning was?

Good news and bad news. The good news is that the slicing went very well, the pre freezing eliminated most of my previous problems. The bad news is that the Costco seasoning was a tad too salty for my taste. And Lew, you were right, the grain changed about 2/3 of the way through. I think that it would have been better if we had just seared when smoked and eaten immediately. Oh well, nothing ventured, nothing gained. You win some, lose some, and some are rained out.

The seasoning could have been okay without the long sous vide. I have found that less is needed when going long. I am not a fan of really salty rubs.

You could be right about saltiness and long sous vide. But my reasoning behind long sous vide, was that given that tri tip has lots of connective tissues, a long sous vide would compensate for places where cross grain was not fully achieved.