ve Freides You are a Deadlift specialist so are focusing your resources on a one rep max Deadlift.
@Antti You are a three Lift Powerlifter and you should be focusing your efforts on a one rep max in Squat, Bench, and Deadlift. I was an Olympic Weightlifter so I drilled the Competition Lifts, a few variations, and Squats. Nothing else, all energy went into improving my total on the platform.
Geoff makes some good points.
One Rep Max Lift Training
As I have mentioned before, one of the training issues of Powerlifters is using the Powerlifts (Squat, Bench Press and Deadlift) as training exercises to increase strength as well as develope technique. Powerlifting appears to be the only sport that fully engages in this protocol.
Other sports, employ weight training as a means of increasing Limit Strength for their sport. They do not employ the sport itself.
Olympic Lifting, Pole Vaulting, etc Lifting For Reps
Olympic Lifters don't preform sets of 10 Reps in the Clean and Jerk or Snatch. Pole Vault for sets of 10 Reps in the vault.
Olympic Lifters employ near max load in the Clean and Jerk for one to two reps.
Pole Vaulters, etc perform one rep at a time, figuratively speaking.
The reason for this is...
Technique Development
Research and empirical data show Technique Development is optimized by training the movement as closely to competition conditions as possible, e.g. Olympic Lifers, Pole Vaulters, Baseball Pitchers, Quaterbacks, etc.
The Traditional Powerlifting Training Protocol Issue
The issue of employing the Powerlifts as Strength Training Exercises is when fatigue set in...
1) Technique deteriorates with each rep.
2) Muscle Activating changes with each rep.
3) Force Production decreases with each rep.
4) Other factors also occur which alters technique.
Ensuring The Development of Technique
Technique is most effectively developed under the following conditions.
1) Performed when fresh in one's training.
2) Performed for single or possibly doubles.
3) Performed with load of at least 80% of your max.
4) Allowing enough rest between each single repetition allowing recovery; it ensures optimal technique.
5) Stopping technique training once fatigue set in.
Developing Strength for Competition Lifts
Auxiliary Exercises that are similar in nature to the lift.
For Olmpic Lifters (Geoff can chime in here), Overhead Pressing, Front and Back Squats, Good Mornings, Glute Ham Bench, Back Raises, Deadlifts, Romanian Deadlifts, etc.
Increasing Strength for Powerlifting Deadlifters: Good Mornings, Hip Extension/Back Raise, Glute Ham Bench, Romanian Deadlift, Glute Bridge, etc. This is the Westside Training Protocol.
The foundation of the Westside Training Protocol and reason for it success is that it built the Olympic Lifting Templet.
For other sports, exercise that work muscles utilized in the sport.
Traditional Powerfiting Training
The traditional method of employing Squat, the Bench Press and Deadlift to increase those Powerlfiters will produce results. However, it is not an optimal training protocol.
At a certain point you need to work on strengthening aspects or portions of you desired goals. How you go about that will be somewhat individual, even though there are specific proven assistance exercises. Correcting technique deficiencies and movement dysfunction is more difficult by yourself and where a coach who knows you is invaluable. You will get there by yourself but it's a longer road.
Assistance Exercises
1) Allow you to increase Strength in the particular lift.
2) Allow you to target a weak point; which bring up another point.
Kenny Croxdale