[xyzzy21]

Honestly if this is a problem, you haven't designed/structured the product design or marketing well enough. You should be focusing on pitching the economics rather than the technical implementation.

And then you want is to have a product plan that makes you essential to the process of productization. If you can't or haven't done that - you indeed run this risk you probably won't get that far.

You want to pitch the market problem, your market solutions without details, and then how you can provide that solution. You do need to be able to "pull out the technical proof" as required but it should not be the center of the pitch.

The other thing to remember: most money people have (relatively) no technical skills sufficient to implement anything they are funding - they are looking to fund an implementor - that's why you would get money. They definitely DO NOT WANT to know the details until you've passed the economic "close" first. Then they may have an industry expert review your technical plan.

For other "exits/deals" like being bought by a large company in the industry, there is actually a bigger risk of pitch-and-run unless the company doesn't current have a presence in the market/technology area or they are looking for a "quick time to market" by buying you. Again you can make yourself essential in an implementor role.

Again focus on the economic need 90%. The technical is usually just a "turn the crank" thing with the right people (paid the right salaries).