I am still working the feasibility of this particular plan, so the details are still fuzzy. Responding to you comments:
1. This is the biggest obstacle of the plan, however, for every IPC the UK spends on warships, the less it is spending on troops to land in Europe or India.
2. This is less than what France starts with, so not necessarily a deal breaker. I also don’t thin it is possible to capture London on a single landing either.
3. France can dump 30 IPC or in Paris as well, not to mention everything else that has fallen back. I also have ruled out SZ 9 as a feasible option. One, you have to deal with mines and to prevent having to move transports back and forth risking mines each time you would have to load through an uncontested Belgium (not easy to keep it that way).
The best option I am considering now is to funnel through Norway with half you transports in your home port and the rest between Scotland and Norway. This option also provides a boost in income. Also, half your transports are better protected. This option also puts pressure on Russia from the north.
As far as your comments regarding Germany’s efforts being hampered in mainland Europe is true, you also don’t have to do as much. You don’t even need to attack France since you don’t need to capture Paris.
Like I said, I am still hammering out the details, but I am favoring 6 transports at the moment. Picking up Denmark, Norway, Sweden, and Finland (12 IPCs) helps offset the expenses.