And for how long could Britain deffend itself? They were running out of Spit's, never mind pilots. Hitler under estimated Brits, its a fact. If LW were taking too long, who knows how long would it take for ground troops? Then USA would step in and Russians would most likely use that advantage to invade Germany?
The LW was depleting faster, and it is questionable how badly the RAF was depleting. You see, the main fight, when the LW faired reasonably well was against RAF's southern system. 10th and 11th group. 12th group did not properly make it into the fight before September, and shone nicely on September the 15th. On September the 16th 1940, the operation Sealion was postponed indefinately due to two things mainly. Those were:
1- The RAF shows itself in growing numbers (which was true)
2- The LW losses are increasing and unacceptable as well as they cannot be replaced fast enough.
The real thing is that the LW never figured out the RAF's group system. 1.200 aircraft + lost in a few weeks and they yet had not figured out.
The BoB might of course never have taken place were it not fur Russian supplied fuel. You should watch the lecture I linked.
Odd enough, Russian patriots often fly off the handle when this theory is aired. I do not see any insult in it. Had I been Stalin, I'd have planned for war against Hitler. Just differently. Well, - there was of course the agenda of world communism....