The reason why so many people have problems with playing in unfamiliar keys is because they are scared of getting out of their comfort zone. It's gonna require them to slow down and really take time to focus to get better at that particular key. I hear excuses like "Why do I have to practice in that key when I can just hit a button? It's much faster." That is pure pyscho-babble!!!
Most people want things done NOW NOW NOW, hardly anyone wants to wait anymore. I just can't figure out why keyboardists can't take time to learn every key when every other instrument player (besides the capo guitarist) has no other choice. It's really a shame b4 God that this is happening.
You can't expect to be a great player in a month, IT'S NOT GONNA HAPPEN. You can't even expect to be a great player in a year, IT'S NOT GONNA HAPPEN. Most of the so-called "great" musicians have at least 10 years of experience under their belt, it didn't happen overnight. You will not see the results of all your hard work until much later down the road, so why not take time out now and learn everything you can?
The sooner we stop making excuses like "that key has awkward fingering" or "that takes too long" and MAN UP, the better off we as musicians will be. Yes, I'm talking to myself as well. It's time out for this foolishness, this is serious business and we should start taking it seriously. God has given us musical gifts & talents that we should be expanding & not sitting down on. Just like it took time to get good in one key, it's gonna take the same (and even more) time to get good in the other ones as well.