The hobglobin of logic: making the facts fit one's conclusion.
(if you have a square peg to fit into a square hole - it will fit but there will be some splinters left

)
The one I find the most interesting is this:
In 1948 the modern Country of Israel was born. Both Daniel and John (in Revelation) mentions 1260 days (which I think is 3½-years) but could be the one day = one year principle could apply. If that is so, it would mean 1260 days.
AD 1948 - 1260 years = AD 688. This was a year in the rise of Islam (followers of Mohammud). It was also one of the some 140 years that the Dome of the Rock (DoR) in Jerusalem was built. Nof when you raise a lots of money over a long period of time (the golden dome is gold sheet pressed over the dome structure - quite expensive) you do things to get rich people to donate. Personally I'd have a dedication every month or so. So surely they dedicated the DoR in AD 688. Anyway, that is how the idea was developed. However, it usually is said like this:
http://www.beholdthebeast.com/mathematical_precision_of_prophecy.htm
(this page has a nice picture of the golden dome of the DoR and these words")
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3. Revelation 12:6 (KJV): And the woman fled into the wilderness, where she hath a place prepared of God, that they should feed her therea thousand two hundred [and] threescore days.[/FONT]
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Most agree that Israel, is the "woman" in the context of this verse. If we then consider that the end of the 1260 "days" was when Israel came out of "the wilderness" (of the people Ezekiel 20:35), or out from being scattered among the nations, returning home and declaring her independence in 1948, and subtract 1260 years ("each day for a year"), we arrive at 688 AD.
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(here it is selling the 'mathematical precision of prophecy' -- Strangely, you won't find this prophetic interpertation until AFTER 1948! They say "Figures don't lie - but liars figure". This is a lying figure, not a proof of 'mathematical precision of prophecy'.
Now if someone had said about AD 1200 that from the building unto the DoR until the an independant Israel was built would be 1260 days - that would be an interesting prophecy. But that didn't happen. Check all you want, the creation of the prophetic 'rumor' was created as 1948 minus 1260.
Prophecies the other way round have Jesus returning in 1844 (adventist movement) or 1988 (Pastor lEdgar C. Whisenant of Arkansas) or whatever -- all DID NOT happen.