It's a limited application technique for sure, but the few times you need it then it comes in handy. If you mostly work flat ground you'll rarely use it. If you can setup a crash pad made out of limbs or a perimeter of blocks to prevent bounce/roll or some combination then that's always going to be quicker and easier for blocking down. Where it has come in to play for me has generally been on steep ground when I was working up in the mountains, particularly if you are working near the edge of a very steep drop off with property below. In those situations you can never establish a decent crash pad/log perimeter and a vertical speedline prevents the blocks from taking off down the hill and causing damage. I'm not a fan of those jobs, they're slow and hard on gear. Generally have no access for a crane, so it's hard work getting the blocks up to the chipper too. When there's no other option, the vertical speedline is an option. I generally set the top of the line with a whoopie sling which is simple to keep taking down as you work the spar down, and tension the system at the base with a roped tie off and then redirected to a porty for easy and quick tensioning of the system. Don't want to make it too tight, the goal is generally just to prevent the blocks taking off. If you plan it right, you can prevent the blocks landing on the ropes that way too.
Shaun
