I do believe the reason for the gaps is that audio tracks do not provide the seeking/positioning information that data tracks do. CDs were originally designed as a streaming format, i.e. an audio CD player's laser basically just jumps in and plays the audio by reading it sequentially.
A CD-ROM/CDRW drive, when reading audio tracks digitally, cannot precisely start/stop at the requested sectors on the disc, there's always an error of up to 1 second (75 frames) plus/minus. This is also why audio extraction can be a difficult and inexact business unless the drive and its firmware are designed to produce accurate DAE (digital audio extraction) at the request of the computer.
As for the gaps - I'm ASSUMING (I could be full of shit right now, don't take my word for it) that the gaps are to ensure that when the drive gets a request to read/play an audio track, it lands somewhere inside the gap when seeking for the start, rather than at the end of a non-audio track, which would cause the drive to abort with an error (expected to find audio, found Mode1 or Mode2 data instead).
Did this make sense? I hope so.
However, I tried to back up my original Final Fight CD [BIN/CUE] just for kicks and it caused the audio to be screwed up. Track 02 actually contained the first two seconds of track 03, track 03 contained the first two seconds of track 04, etc. This did not occur when the gaps were removed from the cue sheet. Any reason for this, you think?
Interesting - if you indeed made a BIN/CUE copy and not an ISO/WAV one, this shouldn't have happened. HOWEVER, I'm wondering whether your disc was one of those that have two indices for each audio track, rather than one. Here's what I mean:
Example of cuesheet for most Saturn games:
Code:
...
TRACK 4 AUDIO
INDEX 01 21:45:07
TRACK 5 AUDIO
INDEX 01 25:16:33 ...
Example of cuesheet for Saturn games with two indices per track:
Code:
...
TRACK 4 AUDIO
INDEX 00 21:43:07
INDEX 01 21:45:07
TRACK 5 AUDIO
INDEX 00 25:14:33
INDEX 01 25:16:33 ...
You may be beginning to see where I'm going with this. Something happened where your burning program and/or drive ignored the zero indices and tacked those two-second bits on to the end of each previous track instead.
Wow! There sure is a lot of potential for confusion here!