When I was preparing to come to Kenya in 2007 I bought a pocket guide to learn Swahili. I wasn’t too serious about practicing, but I do remember sitting on the beach a few times reading that book (I even made flash cards). I’ve gotten pretty good at Swahili over the last few years so I guess it wasn’t a complete waste of time, but there are a lot of phrases you learn when you’re first exposed to Swahili that aren’t really used much by Kenyans themselves.
For instance, there’s a dude at ILRI who always greets me in the morning by saying “Jambo.” Jambo is a polite way to say hi to someone in the sanifu/pure Swahili, but you’ll NEVER hear a Kenyan say it to another Kenyan. My friends always tell me I’m not Kenyan so I should get used to it, but it still gets to me. I always respond, “Poa” (cool), but I guess I haven’t convinced him I actually am cool yet. It’s just that jambo makes me feel like a tourist, an issue I’ve struggled with since I got here.
Another thing you’ll never hear, unless someone is talking about the Lion King, is hakuna matata (no problems) — it’s much more common to hear “hakuna shida,” but it’s all the same I suppose.