Bicycle Mechanics - How important is chain tension on a single speed anyway?

I had to add two links to my ss chain to allow the axel to move rearward enough to allow for knobbie tires and fenders in preparation for winter. Chain tension was perfect before but is now allowing about 1.5 inches of pull down slack even when the axel is in the rear-most position allowed by the drop out.

I was thinking I would have to get a chain tensioner when planning that move but I have ridden about 60 miles on the loose chain without it jumping. So am I still at risk of it jumping? Do I have other problems to worry about now, like premature wear? I am just trying to get a feel for my level of risk by running a slack chain.
Thanks,

Would a half link help? If you have horizontal or semi-horizontal dropouts you don't need a tensioner.

You could ride many many miles with a loose chain and never have if fall off.

The problem Is when you jump a curb. The chain gets thrown almost instantly.

Would a half link help? If you have horizontal or semi-horizontal dropouts you don't need a tensioner.

I have considered the half link (basically 1 link instead of the two required to make normal adjustments, right?). This might be the answer.
Thanks all.

I have considered the half link (basically 1 link instead of the two required to make normal adjustments, right?). This might be the answer.
Thanks all.

Most LBS's don't normally stock half links. You would most likely have to order one.

Most LBS's don't normally stock half links. You would most like have to order one.

Thanks Fixer. I actually just found one at an LBS downtown that deals with fixed gears. I will head down there after work.:)

Doesn't sound like the chain is too loose. Better loose than tight. As long as it doesn't fall off during use, you should be ok.