I saw no issues testing if files aren't there, so we could certainly have that JDR bit enabled if we want.  The most common gc.logs are not rotated and just named gc.log or *.log and so are actually already captured by JDR due to the *.log CollectFiles on line 55.  The *gc.log.* CollectFiles was added specifically for JDR to collect the rotated log file name format used by the script options (gc.log.0, gc.log.1, etc.).

So it'd be a smaller gain.  JDR would then capture default rotated GC log files in addition to the unrotated GC logs that it should already be captured.  Just let me know if we'd prefer it on here.