What Kathy said doesn't make a lot of sense to me about the cycle, because assuming even if he does have a cycle, Sam wasn't examining Clark when he found the mistake, he was looking at the same info sheet Doctor Klein had (I think?). So there could be no indication of a cycle.
Well, you have to read S5 to get the full context. I wasn't saying that Sam discovered Clark's cycle.
In S5, L&C first heard of the cycle's existence when they traveled to the future to return the baby from Family Hour to his rightful parents. While there, they met their youngest child, a son, who was at this point the baby's grandfather. When they were clearly overwhelmed by the fact that they had children at all, the baby's father chuckled and said something like "Ah, I guess you haven't figured out your cycle yet ... yeah, that took me and my wife forever!" The knowledge that they will have children in the future caused Clark to go back to Dr. Klein and ask for more specific information about why he and Lois were incompatible, and that's when he discovered it was a relatively common infertility problem. Around that same time, L&C went undercover in an infertility clinic and allowed someone they trusted to run another test, just to keep up their cover. (After being assured by Dr. Klein that this one test wouldn't give away the fact it was Superman's sperm being tested.) When the test at the clinic tested completely normal, L&C clued in -- this must be the cycle they'd been told about. In other words, depending on the "time of month", Clark's sperm might test incompatible or perfectly normal.
As for what Sam was looking at, though, we really don't know whether he only had Klein's data or he had also run some tests of his own to compare. After all, why would L&C need to let him know that CK=S if he were only going to review Klein's data? If all they needed was a second set of eyes, they could have asked him to "help our friend Superman" or whatever. Certainly, it's greater incentive to have him be helping his daughter and son-in-law, but the implication was that he *had* to know Clark was Superman in order to help them. So I think it's possible he ran his own tests as well.
Kathy
