Conversion of ICE engines to run on hydrogen is what I normally refer to as minor engineering challenge.

On putting it through existing pipelines, I don't know, and don't think you do either, but it would be a luxury in any case, it is transportable by standard well used methods, like fossil fuels, there are vehicles in widespread use transporting it already.

On the statements you've made, you seem to have gone to some effort to avoid comparing directly with the most obvious comparative use case of pipelines; LNG is pumped as gas at low pressure through pipelines. (ie Nordstream before it was blown up).

Embrittlement only happens significantly at high pressures, as does leakage and even then only before liquefaction, so it is not logical to assume it would occur in pipelines, either piped at low pressure, or in liquid form.

Further, its is far from proven, that liquefaction of hydrogen cannot be done at room temperature. Research on this appears to have been suppressed and defunded by it all *being done* by fossil fueled interests previously (It wasn't done).

It displays some bias, when you look for all the impossibilities rather than the possibilities in Engineering, my friend, this is not the trait of a successful Engineer, in my experience. Engineers with this characteristic would tend to not be Engineers very long, imho.

Hehe, I just went and checked your profile, you are obviously an investor, not an Engineer. Everything you think you know about Engineering is imprinted, rather than actually known. Imprintation is required, to be consistently financially rewarded. What do you say about that?