Hi, I don't think you have done your homework.What is the purpose of shooting Raw if that is the case compared to jpeg?
For starters,jpeg is a 8 bit lossy file which means when converting to jpeg by camera sensor it loses some data and if you save file again after photo editing it will recompress and lose data another time until well,the image loses much of it's original quality.
Raw is the original data captured/sensed by camera sensor and is 12/14 bits.When you import to photoshop CS4 it will look like it's is less vibrant and contrasty.Remember if picture has high contrast it has some blown highlights or very dark shadows meaning data is lost from these parts of the image .Raw contains all this information and you can retrieve it to make image outstanding within limits.After you have tweaked the raw file to your expectations then save as TIFF,it's a 16 bit lossless format that will not lose it's data everytime to process it in photoshop,then when you have finalised the picture then you can convert to jpeg and share with others the best result.
Compare 12 bit vesrus 8bit: 8bit colour/greyscale only have 256 levels whereas 12 bit has 4096 levels of data or information or
gradations in shades of colour or greyscale.Do you now know why it is advantageous to shoot Raw? If your camera can produce jpeg in as good a quality as after Raw processing by all means do as it will save you time.It all depends what quality you want for your use or application.If you only save in computer or print 4R then it makes no difference but if you want to print large pictures or use in publishing
then that's a different story.Hope this shed light on your question.PS photoshop can do contrast and sharpening and much more so don't need other software.Get a book to know more and show you.