From a practical point of view, only two things in that speech stood out to me.
1. It will go to a vote in parliament. That's likely to have been what's calmed markets.
2. They aren't looking to remain in the single market and want semi-detached status in the customs union.
So, rather than a Norwegian or Icelandic EEA style model, what she's actually described is something along the lines of a Turkish relationship with the EU, only a bit weaker as she's not really that committed to the customs' union idea, more just a vague wishlist type option.
The only positive I've seen is that she's keen not to rip up the Common Travel Area which would have impacted Ireland very badly. Although, with the UK potentially being outside the customs union and definitely being outside the single market, that relationship is largely going to back to pre-EU days where it only applies to movement of people, not goods or services.
Biting the hand that feeds IT
