Skyman,
I agree with you that, at times, MAN seems to bring out the worst in people. It's a good airport and does, at a stretch, compete with NCL in some of the market segments.
However, there is a simple reason why MAN is not serviced from NCL for their LH & European connections - it is too close to at least 50% of the NCL catchment area.
I live slightly north of Newcastle.
To go to MAN by air to connect:
25 - 35 mins drive to airport
2 hour parking, check-in, security etc.
1 hr flight incl taxy at both ends
20 min arrival and offload period
..and then onto your connection - at least 90 mins ahead.
A Minimum total for LH flight of around 5 hrs 30 mins.
Drive to MAN - a good day 2 hrs 30mins (it is 165 miles from home); a bad day 3 hrs 30 mins.
2 hr 30 mins parking, check-in etc.
On a good day it's better, a bad day about the same.
The cost of fuel against the cost of an air fare, tax etc.
Even worse in terms of flight for EDI and about the same for GLA.
Whilst the EuroStar might not have any impact on us up t'North it will be interesting to see if BRU benefits from London passengers going by train to BRU and then connecting with LH flights rather than the fight through any of the London airports.