Actually, that isn't what the paper says. It clearly concludes that the Luftwaffe had to prevail in the BoB, have a much stronger navy, and extrapolates that a fascist Spain would join in, or at the very least, provide unfettered access to Wehrmacht forces to act against UK interest in the Med. It further notes that the Reich would have needed to have capture of the UK as an operational goal no later than the planning for the Invasion of France.
It has always been agreed that if all these factors existed that See Lowe could be done. The issue has always been, and will continue to be, that there is no way to get all of these factors aligned while having the British, in turn, sit around and wait for the Germans to invade.
There's more. The paper includes the old red herring that if the Germans had continued to attack the airfields, the Luftwaffe would have won the air battle. This ha sbeen debunked so often here and elsewhere that it's very surprising it still circulates at that level.
There's more. The paper correctly sees that the Kriegsmarine was totally outclassed by the Royal Navy, and goes on to recruit the Regia Marina to make things vaguely less desperate for the Axis. Naturally this means that the res tof the summer of 1940 has to go to Gibraltar, and even if assuming that falls (big if), it means that Sealion can't come to pass until 1941 - when the window of weakness of the British Army and fixed fortifications has long gone.
Additionally, it's not just that the
Royal Navy outclassed the Kriegsmarine; it's more like the
Home Fleet outclassed the Kriegsmarine.
You want to add the Regia Marina? Fine, then let's add the Royal Navy forces in the Med, and counting only battleships, battlecruisers and aircraft carriers you have, on September 15, the: Warspite, Valiant, Malaya, Ramillies, Resolution, Renown, Illustrious, Eagle and Ark Royal. To face this, the Italian heavyweights are: Littorio, Vittorio Veneto, Cavour, Cesare, Doria and Duilio. 6 - 6 as to capital ships, 3 - 0 as to carriers.
The bottom line is that the paper has its own points to make, which, mind you, are correct points - but it will shoehorn facts into the framework in order to make them.