I agree with this. It's definitely true and been said in this thread umpteen times, that legally, there's no question the Windsors are rightfully on the throne due to the Act of Settlement.
The "Jacobite succession" is fun to talk and muse about but not to be taken too seriously - like any "alternative history" discussion. It can be fascinating to say "what if?", but the fact is "it didn't".
One final interesting scenario:
Let's say the planned changes to the Succession announced at the CHOGM meeting last month go through and heir's no longer lose their place for
marrying a Roman Catholic and younger sons can't leapfrog older daughters in the line.
And let's say the Duke and Duchess of Cambridge are blessed with a son in 2012 or 2013.
And let's say young Prince Joseph Wenzel of Liechtenstein (born May 24, 1995 in London no less) get married around 2020 and has a child soon after, say a daughter. If he has no more children then the throne of Liechtenstein would have to pass to his brothers but the young daughter would under British law theoretically still be in line for the Jacobite throne notwithstanding the Act of Settlement. So the daughter could not (under Liechtenstein law) become Ruler of Liechtenstein but would hold the Jacobite inheritance.
She then marries the son of TRH The Duke and Duchess of Cambridge (he would by then be allowed to marry an RC) and THE CHILD OF THAT UNION would be a Jacobite claimant on the British throne. (as long as he/she was raised protestant like father and was in Communion with Church of England.
Talk about closing the circle!
Fun to think about.