[harha_]

I'd like to have high speed railways in my country, not some decades long political conversion project. If we need railways that can go across the borders of our neighboring countries, build new ones instead of upgrading existing ones.

[Propelloni]

Upgrading is magnitudes faster than building new. Apparently the current Finnisch idea is to actually build new tracks next to the old one, which requires wider beds, which requires more land, which requires more negotiations. Replacing in situ would be faster, but you would cripple your whole network for the duration.

It's a tradeoff and worthy of deliberation.