Yes, for normal 40-pin IDE cables (used for PIO Modes 1-4 and UltraATA/33), it doesn't really matter if the master is hooked up in the middle of the cable. I used to have 2 UltraATA/33 drives hooked up on a 40-pin cable, with the master in the center, and it worked just fine. No problems whatsoever.
Only the newer 80-pin IDE cables (used for UltraATA/66 and UltraATA/100) seemingly require you to put the UltraATA/66 or 100 device as master at the end of the IDE cable if the other device is UltraATA/33 or slower. This is to prevent the UltraATA/33 drive from slowing down the UltraATA/66 (or higher) drive to UltraATA/33 levels.