@gak
Let me see if I can give you a quick answer. I'm assuming that your wife's employment as a teacher is not covered by Social Security because she did not have SS taxes with held. I'm also assuming that your wife will have 40 quarters of credit based on non-teaching earnings on which Social Security taxes were paid.
First, you own benefit as a lifetime earner under Social Security will not be cut. Looking at a public teachers' website I saw a lot of misinformation, exaggeration, and pure nonsense about the subjects of GPO and WEP. Don't believe anything you hear from teachers on the subject -- get accurate information. Which it looks like you're trying to do by studying the material at the links you gave.
Let's look at a couple of possible scenarios:
When both you and your wife are retired, for your wife the SS Administration would look at spousal benefits which are approximately 50% of yours. GPO would apply. For every 3 dollars of her teacher's pension, they take away 2 dollars of her spousal benefit, but the spousal benefit does not go below zero. Then they look at her benefit from her own earnings covered by Social Security. Benefits are computed based on the average of the highest 35 years of indexed lifetime earnings. At the Normal Retirement Age, the first $680 of monthly earnings is replaced at the rate of 90%, the next $3420 is replaced at the rate of 32%, and anything beyond that is replaced at the rate of 15%. Since she probably will have less than 21 years of Substantial Earnings under Social Security, then WEP would apply. Instead of 90% of the first $680 she would get 40%. This is still a better deal than the average earner under Social Security who gets only a 32% return for working a bit extra and quite a bit higher for the top earner under Social Security who only gets 1% for working extra. Of the two possible benefit amounts, whether spousal benefits reduced by GPO or her own benefit reduced by WEP, she will get the higher. In the meantime, as a lifetime earner under SS, you get your own full benefit totally unaffected by either WEP or GPO. So as a couple you get your full benefit, her teacher's pension, and she also receives some benefit from SS.
Let's say that you die first. In that case, her spousal benefit becomes whatever your benefit was, except that GPO still applies. After reducing that by 2/3 of her pension, if it's higher than her own benefit reduced by WEP then she will get the higher benefit. In this case, your wife continues to receive her teachers pension and a SS benefit which may increase.
Hopefully this will get you started to a more accurate understanding of WEP and GPO. Another source of information is http://www.ssa.gov/gpo-wep/.
