Delay backup-on-mount for Time Machine drives?

[Spyder]

I'm using my Time Machine drive as the SuperDuper! target, after prior experience showed managing the split between SD and TM partitions to be a pain in the arse (I have a 500gb main drive, and don't want to dedicate a 500gb partition to SD as it's rarely full).

Everything is working, but if the drive has been unplugged for more than an hour both SD and Time Machine start up as soon as it's plugged in. This makes both horribly slow :(

Is there any way for SD to load, but not start the copy process immediately? Or detect when TM is backing up (which will slow down access to the SD source drive regardless of where TM is targetting) and pause the copy process?

[dnanian]

I've not found that SD! and TM running simultaneously causes significant slowdowns. TM runs with low-priority, so it'll slow down automatically while SD! is accessing the drive, and speed up when it's done...

[Spyder]

I thought TM was slow because they were fighting for disk bandwidth. I've just discovered that DropBox is actually what makes my system slow while SD! runs (http://forums.getdropbox.com/topic.php?id=9709&replies=7), ditching that plus the recent speed upgrade should make things better. I'll keep an eye on it, thanks :)