I remember reading (possibly in Evolution of Desire by David M. Buss) that in something like 95% of the cases a male's gut instinct is right when they feel their partner is committing infidelity.

Answering as someone almost 40: NO.

Never trust a woman. Always have a backup plan. She will screw you over someday.

That said, you really can't trust anyone. Friends will eventually let you down. Family will eventually let you down.

That said, never make the mistake of thinking women want the same things out of life as men. Her goals are assuredly not your goals.

A scorpion was walking along the bank of a river, wondering how to get to the other side. Suddenly, he saw a fox. He asked the fox to take him on his back across the river. The fox said, "No. If I do that, you'll sting me, and I'll drown." The scorpion assured him, "If I do that, we'll both drown." The fox thought about it and finally agreed. So the scorpion climbed up on his back, and the fox began to swim. But halfway across the river, the scorpion stung him. As poison filled his veins, the fox turned to the scorpion and said, "Why did you do that? Now you'll drown, too." "I couldn't help it," said the scorpion. "It's my nature."

Woman are ruled by emotions and seek immediate gratification, as said earlier in this tread "trust a woman to be a woman", and don't put your self in situations were a woman acting like a woman will screw you.

been married for 12 years and I trust my wife completely. There are a ton of key ingredients to that trust though. Picking properly, setting ground rules, maintaining her desire for you etc etc.

Here is the thing about long term relationships that I think most overlook. It is all about training each other in a similar way you would a dog. You learn each other in and out. You have to make sure she understands the consequences of disobedience to the rules of the relationship.

You can trust them to be women.

Trust, but verify. It's up to you how much you want to verify. Monitor the home network for suspicious behaviors (browser history erased? Dating sites?), buy her a new cell as a gift and bundle on your contract to watch for texting history, outright ask her leading questions you know the answers to, etc. Watch for red flags.

Yes I trust them to follow their nature/body agenda.

Yes, more so now as I have a better understanding of how they tick

No, I don't trust women, at least when it comes to relationships. Although to be honest, I never did even before swallowing TRP.

As much as I trust my dog not to bite me when I try to take away a plate of food he's eating from...