I am at heart a mathematician so don't assume what follows has anything to do with personal leanings.
MrBishop said:
"If gays were allowed to be married, this would allow them to adopt. It is well known that despite the fact that only 1% of the population is gay, that 50% of pedophiles are gay"
" In a recent survey amongst convicted pedophiliac, over 80% said that they were heterosexual and preferred sex with the opposite sex (adult) when they could get it. That's a mere 20% for homosexuals... "
Let's look at these numbers, hmm? 1% of pop'n being gay means straight people outnumber gay by 99 to 1. Your statistic on paedophiles gives a ratio of 4:1. 20% of the paedophile pop'n vs 1% of the global pop'n isn't a great figure - that's an increase of 2000%.
Take, say, 10,000 people - by the figures, 100 of these people are gay. Now, let's assume that 0.5% of the population are paedophiles ( I have no idea what the actual value is). That means that 50 people out of this 10000 are paedophiles. Now, 80% of this 50 are straight - 40 people, and 20% are gay - 10 people. That means that 10/100 = 10% of the gay population are paedophiles, as opposed to 40/9900 = 0.4% of the straight population. Those aren't great numbers.
Even taking a more generous figure of 10% homosexual in the population (personally I feel that the 1% stated earlier is probably not far from the truth), that gives a result that 1% of the gay population is paedophilic - which means that a homosexual is 2.5X more likely to be a paedophile than is a straight man.
Now, I'm not saying anything more than the fact that given these numbers and the fact that people are insanely stupid, it's not hard to see where people get the sort of conclusions you were objecting to.