mate with two bishops

i am beginning to understand the check mate with two bishops.

once the oposing king is on the edge file or rank, is there is an optimum place for my king?

if i want to checkmate on A1 am i right in think my king on C3 is the optimum place?  as it leaves on A3 and C1 as flight squares .

that is the main position mate in 1 for white but basically the strategey is cut off his escape squares with your bishop and king and then force him into the square where your bishop can check him for mate

There are many videos going over this checkmate:

http://www.youtube.com/watch?v=YHJqBilVLPU

http://www.youtube.com/watch?v=uimbIq9h_7A

http://www.chessvideos.tv/forum/viewtopic.php?t=293

http://www.youtube.com/watch?v=cA3c1ORODsw

To fully understand this endgame, you need a method that will work from any position.  I like to think of the process in three steps.

1. take control of the center

2.drive the King to the edge

3. drive the King to a corner and deliver mate.

Depending on the position, Steps 1 or 2 may already be achieved. Just thinking of the process in this way will help you select good moves that drive the ending efficiently.

thank you everyone.

1. :white= Rb5 ,Rb6 and Kc7 black = Ka8# 
2. :white= Rg5 ,Rg6 and Kf7 black = Kh8#
3. :white= Rb4 ,Rb3 and Kc2 black = Ka1#
4. :white= Rg4 ,Rg3 and Kf2 black = Kh1#

could someone tell me if these are all viable checkmates ?