Firstly I wish to excuse my English...this is responsible for the misunderstanding! What I meant by "For example, we know that at least 12% of English is from Greek,( 35% according to some linguists), and we dont have any evidence for most of that, but does that mean it is not a fact?" is that: Even if we dont have evidence for how some Greek words reached the english language, it doesnt change the fact that indeed they came from Greek, mainly because they were used in Greek long before they reached english (or any other language). Now, about 'Harrys', I didnt claim in any of my previous posts that the English 'Harry' came from Greek 'Harrys'. All I said is that 'Harry' is indeed closer to Greek 'Harrys' than to Norman 'Henry'...and isn't that a fact???
PS: I had the precious help of an English friend to write this, whose father's name coincidently is Harry and he wished his name came from Greek because in Greek it means 'attractive'! :)