Depth Jump Rules for Old Dudes

I was first introduced to depth jumps in high school. It was part of a basketball training program at my first high school. We weren't given any explanation on how to perform the exercise and our coach had all of us dropping off a table that was at least 30 inches off the floor on our very first day. Needless to say, I really didn't see any improvement using this exercise and I thought it was kind of stupid.
With the Jump Soles program, I performed depth jumps 3 times a week. The program, at the time, didn't come with a great deal of instruction and, looking back, I know that I didn't perform this exercise correctly. Again, because of poor technique, I thought the exercise wasn't very useful.
When I put together my squat/depth jump program a few years later, I read a more about depth jumps in some volleyball magazines that gave better instruction on how to perform the exercise. This time I saw a great improvement in my vertical and started to love this exercise. One thing I did was start from a low box and then work my way up to a 24 inch box over the course of a few weeks. I really learned how to explode through my jumps starting this way.
In college, I performed depth jumps sporadically. It wasn't until I used the Science of Jumping program that I starting using them again on a regular basis. At that time, I wasn't jumping really high and could dunk with two hands off of a drop-step. It wasn't until the past few years that I stopped using them. During this time, I've had a few injuries that have frustrated me (leg stress fractures, partially torn Achilles tendon, hip strain, tendinitis) and have not allowed me to perform depth jumps like I used to perform them. The issue is that I tried to perform them like I did when I was younger, using lots of resp multiple times a week on high boxes.
With my current training, I am going to follow  a set of rules and see if I can not only perform depth jumps without causing tendinitis and still see an increase in my vertical jump. Here are my "old dude rules for depth jumps":

1. Soft surfaces only. No concrete or basketball courts. Either grass, sand, or on a stack of mats.
2. Only one day per week. I'll need to give my legs lots of time to recover.
3. Start slow and low. I've started this program performing only drop jumps off a low box. In the coming weeks, I'll switch to depth jumps off a low box and won't transition to a higher box for at least a few weeks. 
4. Lower rep sets. No more than 5 reps per set. 
5. Soft landings after each jump.

Since depth jumps have always been a part of my training when I was jumping really high, I've got to find a way to keep doing them.

C