I'm sure Jake is right but
 

you can go broke changing/improving every little bit to decrease your probability of failures. Not to mention the added potential for problems caused by mechanics error.

It makes sense in F1 racing...but on my car?

Recall that Jake says there are 21-22 failure modes. Does it make economic sense for every M96 owner to go try and prevent them all?

Where do you start and stop? How do I know what is the risk of failure and how do I know what is the risk of spending to fix problems I won't have?

If I just look at Jake's 'cpo" list of fixes that starts to add up to some serious money and it improves your chances how much? And leaves how many potential failure modes? And how many yet undiscovered? After all the guy who had #21 could have had an engine with 20 fixes and it still failed.

How do you prove to yourself that just letting it fail and buying a used/"cpo"/new engine when/if it does isn't a better economic decision?

How many of the recommended fixes are said to have to be done again in some number of years/miles? IMSR/AOS/water-pump...what else?

I've spent thousands on cars over the years improving things that only got sold on to the next guy for no added money. Why not just take your chances?

I know that a lot of these questions don't have answers and I mean no disrespect to Jake when I use his name in asking them. Nor do I expect him to have answers. I doubt Porsche does. I only present the questions to cast some doubt that the answer is as black or white as some may make it out to be...it sure is gray to me.

+1 on that, Mike. When I first started reading the forum I had this list going - AOS, MAF, O2 sensors, water pump, clutch.....and on up to about 4 or 5 grand by the time I was done. Then I realized I was breaking one of my main rules - if it ain't broke, don't fix it. Decided I'll fix things when and if they break and I'll probably save a fortune - after all the car could get written off tomorrow and all that time and money would have been for naught. Chasing what might break can work out to be pretty expensive insurance.

I think there are a couple of exceptions to this: I buy into what Jake is saying about water pumps - results don't lie. I will also upgrade my IMS bearing, but only when I need to go in there anyway for an rms or clutch and, like most people, I'll do all three at that time. The gamble here is that the IMS won't be the first of the three to fail.

If I'm one of the unlucky ones that has one of those engine-destroying failures, that will be my excuse to replace it with some serious horsepower. It's an ill wind that blows no good!

And in another thread somewhere
 

Jake said there are several makers of OEM water pumps and one is better than the others.

So the decision making gets more complicated:

Ignore
Replace with NAPA rebuilt
Replace with NAPA new
Replace with any OEM
Replace with Jake's special OEM.

What he didn't say is which brand of oem pump is better, or why it's better. And, if you're going to replace it every three years anyway, how much better does it really need to be?

This water pump business is indeed rather complicated.

Water pump and t-stat replacement difficulty
 

Okay so let's assume we have the best replacement pump and t-stat. How problematic is this job? I would have to do it on ramps or jackstands