I think you will find in general a huge variety of ways of practising as well as of teaching under the Aikikai "umbrella".
My personal experience is that within the Aikikai "muscling thru it" is generally regarded as bad aikido. I don't know your level of experience, but in my opinion it is not always easy at an early level to tell the difference between technically excellent aikido, aikido performed with inner power, and aikido where uke falls too easily (either to make tori look or feel better or simply through habit).
My only time watching a ki aikido class (just one sample, so it is probably not representative) was disappointing - after all the ki exercises in the first part of the class I was expecting superior aikido, but what I did see was surprisingly scrappy and looked pretty ineffective. However, I have been in a couple of classes with Koretoshi Maruyama Sensei (ex-Ki Society), and found him deeply impressive, As I said, there is a lot of variation wherever you go.
I'm not sure either what you mean by "how to apply KI". I'm not convinced that Tohei Sensei's guidelines and the exercises he taught are the same thing as what is often referred to on AikiWeb as "kokyu skills", but that's a whole different discussion.
Alex thanks for your input. I would have to agree to a certain extent. Coming from the Ki Aikido side, it does seem that some just go thru the motion and just fall. However, I have seen some Shin Shin Toitsu Aikido practioners really ensure the extension of Ki is very effective (with painful results on the receiving end). I just can't believe how different the approach is sometimes. When I studied with the Honolulu Ki society, We had some Aikikai Students attend from Japan. It was cool to get a different perspective, but the whole principle of KI seemed almost alien to them, as compared to the level Tohei Sensei instilled in his KI Aikido. Ki Aikido is so soft in nature, many Aikido practitioners dismiss this style all together. I personally have never practiced Aikikai Aikido, so to speculate would not be accurate or fair. It looks real cool, and more harder in nature. The question is, can the extreame soft style of KI Aikido be just as effective in the street as Aikikai Aikido?
May God Bless!