chotenet and chamot

In this week's parsha, Yitro is referred to as the choten חותן of Moshe - his father-in-law. In proper Hebrew, there is are different terms for the husband's parents and the wife's parents. Until I started writing this - I could never remember which was which. When I would refer to my inlaws in Hebrew, I would avoid the issue by saying "my wife's mother" or "my wife's father". But now I have a public forum and I need to know what's what.

Safa-Ivrit does a good job of explaining the issue. To summarize - choten and chotenet חותנת are the wife's parents, and cham חם and chamot חמות are the husband's parents. The site offers this tip to remember which is which - the choten and chotenet marry off - mechatnim מחתנים - their daughter, and the cham and chamot welcome their new daughter-in-law warmly - b'chom בחום.
Chamot has the same structure as achot אחות - sister. So while it sounds plural, it's really singular. (So the joke about שפך חמתך (shfoch chamat'cha) being an excuse to throw your mother-in-law out of the house during the seder doesn't work - it would need to be שפך חמותך - shfoch chamot'cha.)

In any case, if you do mix it up, you don't need to worry much. Even in the time of the Talmud, there were cases where the distinction was blurred.

Now everyone agrees that the word for son-in-law is chatan. However, years ago I came across a pamphlet that was trying to show how Jastrow's dictionary was not a serious work. (Perhaps it was this one by Shlomo Alter Halperin? I really don't recall.) The only proof that I remember was from Jastrow's definition of chatan, where he writes: "connection, son-in-law; bride-groom". The author of the pamphlet claimed that Jastrow was including a Yiddishism, apparently as a joke. I didn't understand the argument then - and I certainly have trouble now, not having seen it in print in years. Do any of the readers have the pamphlet, or otherwise understand the argument?