Sorry for snipping your reply but this is the part I found interesting and wanted to comment on. How do "we" know the above is true? From stats or personal experiences or hearsay? I am just curious because the three things mentioned above really don't amount to a hill of beans if the people show their relationship is real. If you get my meaning, EVERYTHING and ANYTHING is a red flag if you don't address it.
If the couple has a 20 year age gap and comes from two different religions and one is white one is black and one is a Ph.D. and one never finished high school does that mean they aren't in love or don't have a real marriage? They might in fact have been married for 10 years have 3 kids and have the best marriage anyone has known...
I would hope that the VO working on these applications don't simply look at any one or two things create a profile in their minds of why the application is not real and never do their homework. Even if they see what is being called a red flag IF the people in question are legit they will be able to prove it and that really is the main thing to keep in mind. If you "KNOW" you are the real deal don't let all the little red flags so forth and so on weigh on you, just make the effort to document the reality of your life and follow the application through to the end.