[Sashimister]

Originally Posted by Nyororin

No matter how I try to come up with a good situation, かれたち just sounds... weird.

I honestly cannot think of a normal situation using it. It isn`t wrong, but it carries a different feeling than かれら which I would consider "natural". Even in a more formal situation.

かれたち makes me think of referring to boyfriends...

I completely agree with this.

I don't think I've ever said かれたち in my life. I may have heard it said but you hear many things said if you live half a century.

かれら is the pronoun I would use if I had to use a pronoun. However,　I'd much rather act like a Japanese and use あの人たち or　～～さんたち.

In Japan, you will hear かれら most often in the English classes in junior high and high schools when they have to translate the word "they" into Japanese.

Originally Posted by KyleGoetz

I back up what MMM said. I have this strange feeling that teeeechnically you would say something like ピザの食べることができる instead of ピザを, although using を is perfectly acceptable. I always use を, but I just had this feeling like maybe I learned の or が is "more correct" seven years ago in my classes.

We don't say ピザの食べることができる in any situation. 　が is also incorrect. It's ピザを.

However, you can say in a relative clause:
ピザを食べることのできる店 　
The の here is preferred over が.