“If they can reach an agreement it would be a huge home run as we have so many UK visitors and there is still a lagging perception about the entry process which may be putting people off.”The solution discussed at the link resembles the Global Entry program but with reciprocity. Of course biometrics will be involved.
A bilateral agreement between countries that share a high volume of traffic, good information sharing, and a high confidence in the other's ID management rigor might significantly improve border efficiency.
Border issues have been a big deal in the UK lately. The recent Border Scandal and concerns over throughput at busy times combined with a certain upcoming quadrennial event have kept the Border Agency's attention on ways to improve.