-Shock Loading How important is it?

[sanddrag]

I've actually never heard of the method you're describing
There is a risk factor of having a drivetrain without the shock loading system but as long as it is built robustly, it should be okay. We have never had problems with sprockets and chains. I don't thinks you could really break a chain link or sprocket tooth wery easily. However, we ahve had problems in a couple other areas. We mounted our drill motors with 6-32 threaded rod and connected them with the SPI drive couplers. Under extreme abuse the couplers came loose and the threaded rod flexed. However, this was the least of our concerns. We were using 32P Brass gears from SPI and those stripped and broke like crazy. As long as you use Steel 20P gears from Boston Gear or sprockets and chains, you should be alright. Also, keep the chains straight and tight and maybe a little slippage with the tires isn't such a bad thing. It will be easier to turn and won't be suck a shock when going instantly from full speed to stopped such as when runing into something. Hope this helps.