It does get annoying I've been having trouble just trying to get just two bots to reliably use the stretch/fix technique, couldn't imagine attempting it with a mass of bots. Could you post what you've done so far, it'd help figuring out what's going on.
You could look at my bot caterpillar for proper tie-movement with just two bots. You coud also look at the example welwordian just posted. Second link(altrough that seems to be out of sync a little, lot of vibration)
You can ignore *.move, the *.head is for the bot that has the lead. (you can also replace it with something like (*.trefage *.robage <)) to define the oldest bot every time as head.
*.time is specified on birth, it is the time of a whole tie strech/fix cycle. Best somewhere between 10 and 20.
*.maxlengh is a way to control speed.
*.stiftie should be just high, I'd gues between 50 and 100.
Here is the specific tie section.
'------tie-moving stuff
'second step body
cond
*.move 1 !=
*.head 0 =
*.trefage *.time mod *.time 2 div >
start
*.maxlengh .fixlen store
1 .fixpos store
stop
'second step head
cond
*.move 1 !=
*.head 0 !=
*.robage *.time mod *.time 2 div >
start
0 .fixpos store
stop
'first step body
cond
*.move 1 !=
*.head 0 =
*.trefage *.time mod *.time 2 div <
start
1 .fixlen store
0 .fixpos store
stop
'second step head
cond
*.move 1 !=
*.head 0 !=
*.robage *.time mod *.time 2 div <
start
1 .fixpos store
stop
Welwordion, I too don't know.
It keeps kind of hard to create something like that, there are a lot of little stuff that can go wrong.