Developing language and working phrases or licks through keys is part of the time-honored tradition of jazz improvisation. This seems to hearken back to Charlie Parker getting tossed off the band stand as he was shredding through Honeysuckle Rose at a Kansas City Jam Session....in the wrong key! Parker had developed language, but had yet to transfer that language to a variety of keys, a mistake he wouldn't make twice!
So a question that is often asked is, how many keys should I learn ideas in? Do I need to learn them in 12 keys? The short answer is - learn them in as many as you can. I say that with tongue slightly in cheek. Here is the bottom line - learning phrases in 12 keys is great, it is preferred. You will get the most out of the process and develop the most technique across your instrument and probably develop a better ear. BUT. There is a big but here, because I have also encountered students who are so intimidated or frustrated by twelve-keying a lick that they abandon the whole process all together. Well, better to 5-key or even 3-key a lick and get something out of it than cower at the challenge of a 12-keyed lick.
This is the exact reason why the improvisation guides found in the members only section specify the exact keys that students need to learn various language in. (Shameless plug, but maybe not so shameless, its my blog). Working with jazz language on a specific tune may require learning a lick in 3 keys, but working on a different tune may add two additional keys to that sum - so now we have 5-keyed a lick and been able to apply it to the appropriate spot in solos
There are a variety of ways to learn language through key centers. Many young jazz musicians rush to their knowledge of theory to transpose a lick. They figure out the various scale degrees and then simply attempt to realize those scale degrees in the new key. That is okay, but I prefer to use that as strategy number two. This is still an aural art form and multi-keying a lick is still somewhat about training the ear. So, I would stay away from the theory at first and approach the process like you are transcribing the lick in each key. Sing it, play it. Work to figure it out with your ear. Finally, when you get into a jam and can't "ear" your way out of it, then use the theory as your second strategy.
So, 3-key or 5-key, what is recommended. Do what you can. More keys are always better, but don't abandoned the process altogether just because we can't get through all of them yet!