A very nice basis for a campaign: it's a long decision tree which will result in some historical or historically plausible battles without, for example, the Royal Navy attempting to force its way past Denmark into the Baltic (one of Churchill's suggestions vetoed on the grounds of its suicidal nature!)
The historical reluctance of the Kreigsmarine to risk too much despite this meaning they sink fewer ships is covered by some battles possibly having major Royal Navy units turn up late on in battles, and a 'quit rather than sticking around' table.
The whole thing is also mostly rule system neutral apart from the way that, like Naval Thunder, it does not state the scale anywhere - all the distances are in tabletop inches, and times in 'turns'.
Looking at Steel Dreadnought's quiet forum suggests it's 1" = 500 yards and one turn is four minutes, but it would have been far better to have had the ranges in yards and had times in so many minutes in the first place.
[5 of 5 Stars!]