Why would you, the customer, want to change the interleave value?  When the 
computer manufacturer initialized the computer system, there was no tape drive 
installed as there is now.  The tape drive, when operating, uses the computer's 
memory at almost the exact same time as the hard disk does.  This causes the 
computer to not be able to supply or accept data from the hard disk as fast as 
it would when the tape drive is not running.  (Note: you may or may not have a 
tape drive installed, depending on where you got this program).

Note: The tape has to actually be moving before it slows down your system, 
don't worry!  

An easy way to see if you need to adjust your interleave is by running your 
tape backup program, and performing an IMAGE BACKUP.  Listen to the tape drive 
as the program runs.  If the tape runs for a long time before stopping, your 
computer is probably just fine the way it is.  If the drive stops for a moment 
every 5 to 15 seconds, you probably need to change the interleave.  

By increasing the interleave from the factory value (usually 2, or 3) your 
computer will be able to handle the requirements of having two high-speed 
devices being used at the same time, instead of just one.  

Our tests have shown that a good value for interleave is FIVE.  This should 
give you nearly identical performance with your other programs (spreadsheets, 
BASIC, and so on), but will help the tape drive to receive and transmit in a 
smooth, streaming manner.  

If you want to select a different interleave value, you specify it on the 
command line, such as IAU 3 <cr>.   Permissable values are from 1 to 15.  
Typical values are from 2 to 6.

This interleave-changing program is specially designed so that none of the data 
you have on your disk will be altered during the operation.  All of the 
programs that we had seen wipe out the data on the disk whenever the interleave 
value is changed.  That's why we wrote this program for our customers.  

Please be sure to read the WARNING MESSAGE before you start the re-interleave 
operation.