Where did you read about Churchill getting the trench warfare device idea from Wells? I think I know what you're talking about; Churchill mentions it in his memoirs of WWII; it was developed under a secret identity as a piece of agricultural equipment (cultivator #8 I think). The basic idea was that it was an earthmoving tank that would dig a trench across no-man's-land very quickly and allow troops to attack without dealing with all that tedious barbed-wire and machine-gun nonsense.
It wasn't that it was developed too late in the war, though; it was just that blitzkrieg warfare rendered trench warfare and all appurtaining technologies obsolete. Is this what you are talking about?
'Door into Summer' shows the positive side of patents, but Heinlein had a couple of anti-patent points also. He argued that sometimes not using a patent was more socially responsible or practical when dealing with a large entrenched corporate monopoly.
In 'let there be light', two scientists invent a serviceable 99% efficient solar panel. Rather than attempting to patent their discovery and get snarled up in the courts by the power syndicate's stagnatogenic lawsuits trying to keep their competition at bay, the scientists opt to open-source it instead and get married.
From the other perspective, there's 'Friday'. RAH points out that any company with a truly revolutionary product they want to maintain control over is better off keeping the blueprints proprietary and not patenting it. The idea is that if you patent it then everyone will know your secret and knock-offs will start springing up in no time. If the technology is sufficiently complex and abstruse, though, you don't need to worry about it being reverse-engineered. RAH came up with the 'Shipstone' company, which manufactured black-box, extremely efficient energy storage batteries, which they parlayed into a global hegemony by hooking them up to the aforementioned solar panels (I love how Heinlein is always referring back to himself).
So I guess the point is that patents are okay for little stuff, but for Grand Tech it's kind of a superfluity; either the secrets of the invention is shared with the world, or it isn't.
