QUOTE(kerioboe @ Feb 7 2007, 08:19 AM)

In an exam you can just wizz up and down the scale and just listen to make sure the pattern is right. When you are playing music, however, you need to be able to recognise and play a scale starting and ending on any note. (What I mean is the piece may have a bit of an E major scale, for example, starting on C# and finishing on B for example). To do this you cannot rely just on the overall sound of the scale pattern and having the finger patterns fluently under your fingers is only helpful if you can instantly start and stop whenever you want. Also, as someone else has said, knowing how many sharps and flats there are in the differenty keys helps considerably when sight-reading.
it's a very good point Kerioboe.
... about playing a scale in a particular key but not necessarily starting on the tonic!
There is a brilliant book* for sax players (and the idea clearly can be adapted for other instruments) which shows scales in all keys and starting on all possible notes of the scale. It's quite a big volume, but so comprehensive that if you use it conscientiously what amazing technique you would have.
I have found from time to time that I choose a key to work in for that practice session, play some of the exercises and then perhaps I make a slip up; so I start again and I can't play it. In other words, let's say it's Eb major day, I suddenly find I struggle to play Eb major if I have to start on any note other than the tonic. It seems like a scale I've not seen before!! To me it means I don't know it well enough
and how often do composers help us by putting scales that start on the tonic into their compositions?
* It's a great book for sax players, by ... .... . . . Joe Viola