Reference on less common trad mistakes ?

This example shows protection pieces working against each other due to a bad combination of force angles in the event of a fall.  I'm looking for other similarly unusual things to watch out for.

Basic rock craft by royal robbins is good also the trade climbers bible.

The most obvious although a very common trad climbing mistake is to use a single rope where half ropes are the obvious choice (e.g., the OP's image).

I'm staring at that drawing and wondering why anyone would do that? To back up a marginal placement with a second marginal placement, or an attempt to equalize two bad placements? It's hard to imagine when this would be your only option. 

One solution if this was really your only option would be to extend the right sling and wrap it through the left sling's 'biner like you would with two opposing nuts, so that the rope is clipped into a single 'biner lower than the two placements, which would at least reduce the force multiplication on the two pieces. Or just use longer slings on both placements.

+1 for Robbins' Advanced Rock Craft to learn about equalizing marginal pieces.

I'm staring at that drawing and all I see is Ondra.

At the risk of derailing: how useful is Freedom of the Hills for someone primarily interested in free trad rock climbing without alpine aspects (no cold/ice/snow)? I hear it mentioned frequently but every time I look at the Amazon page it seems like it's geared toward alpinism.

David Kerkeslager wrote:

sometimes it's best to look into what TO DO instead of what not to do.  There is a good book out there by Topher Donahue "Advanced Rock Climbing"   can't go wrong with that, and the discussion in the text details the rationale of expert climbing techniques. 

Serge Smirnov wrote:

Can anyone recommend a book or online reference that attempts to list as many as possible of the mistakes one can make while leading ?

Follow each other's leads a lot with a pact to critique the hell out of each other and ourselves.  There is so much to learn.

Amazon,  Tons of books

Serge Smirnov wrote:

This example shows protection pieces working against each other due to a bad combination of force angles in the event of a fall.  I'm looking for other similarly unusual things to watch out for.

"due to a bad combination of force angles"? I'd assume they were two opposed pieces deliberately set that way because that's what was availablle. What's the problem?

Bill Czajkowski wrote:

"due to a bad combination of force angles"? I'd assume they were two opposed pieces deliberately set that way because that's what was availablle. What's the problem?

Agreed- I would be more concerned about getting flipped upside down by the slings than the pieces working against each other, unless they weren't properly extended

Hm, you guys are right - the angle wouldn't be as bad as I initially thought.  Bad example on my part.

Serge Smirnov wrote:

Hm, you guys are right - the angle wouldn't be as bad as I initially thought.  Bad example on my part.

Well, the angle isn't good but when that's the only way to rig it, generally you'll take it. You'd want to reassure yourself that the rock is strong enough to hold and I would want a reasonable amount of rope out to lessen the impact force. However, it is a well endorsed technique. I probably wouldn't connect the slings like it is done in the diagram however.

I'm surprised no-one has mentioned "Trad Climbers Bible" from the gospel of Peter and John.

It's a storytelling oriented collection of difficult 'lessons' learned for trad climbers. It doesn't cover skills but focuses on judgement, making decisions and all the other good stuff most books glaze over, which makes a climber competent. It's also a very entertaining read.

ebmudder wrote:

I'm staring at that drawing and wondering why anyone would do that? To back up a marginal placement with a second marginal placement,

When you climb a route that really has no pro and you want "mental "pro. Just did this on a route that otherwise would have had me 60 feet above my last good piece. 

Leslie McG wrote:

When you climb a route that really has no pro and you want "mental "pro. Just did this on a route that otherwise would have had me 60 feet above my last good piece. 

If you used longer slings then your piece wouldn't be loaded straight outward and might have better odds of actually doing something

IcePick wrote:

I'm staring at that drawing and all I see is Ondra.

No neck. Can't be Ondra.

eli poss wrote:

If you used longer slings then your piece wouldn't be loaded straight outward and might have better odds of actually doing something

I extend all my pieces unless the route is straight. I'll take the extra distance of falling over rope drag any day! 

one trick for dealing with the situation shown in the photo, assuming you are only using one rope, is to tie into both ends of the rope and climb the pitch as you normally would with doubles.  ie, use one rope with the gear on the left and one rope with the gear on the right.  if this is on a multipitch route, the belayer/second would just tie into the middle of the route and the leader would belay them up on both ropes.  this is a really handy trick for dealing with big traversing crack switches, etc.