Compared to whatever 'standard' lifting program, if it's supposed to complement grappling, I would - not use low rep ranges - use way more unilateral work than those - try to taylor it's focus to best prevent injuries that this specific person tends to get in grappling (e.g. in my case - I tend to get minor hamstring tears, never quad tears so I'd choose leg focus accordingly)

It still depends on what the goals are. If you're trying to develop 'strength' going over 5 reps is usually going to hinder that somewhat. If you're trying to grow muscle it's more about total volume If you're trying to just prevent injuries then you need to grow strength in movements/muscles that are susceptible depending on the way you play... I wouldn't say it's about rep-ranges, more addressing the issues at hand. Hamstring injuries occur when weak/tight hamstrings are stretched and contracted beyond their capabilities. Now, as far as beating yourself up from training, the best thing you can do is condition your body aerobically to handle to load AND stay away from failure... you could even go as far as stopping as soon as you feel reps start to slow down. Well, there is my first post on Beltchecker

I do a 5x5 weight training programme, kettlebells, bodyweight, joint mobility, etc. because I'm old and injured.

I'd advise against 5x5 because 5 rep range demands that you use higher weights which are harder on your joints. If you switch for 3x10-15 or even 2x20 you can reduce the weigh significantly and save your tendons. Even dedicated power lifters can only do 5x5 for a mesocycle at a time.

5x5 is just fine if you don't go past 80%. And really, it's not about amount of reps, but the quality of reps and time under tension. That 3x10 or 2x20 just leads to fatique, which is not what we want. You can of course rep out if you use baby weights, but those don't give any gains in strength.

You guys could be interested in this concept I've used with athletes in-season (I work with Rugby Players) called hypertrophy clusters. I've started applying it to bjj too, and could even work great as energy system training. Essentially you take the same weight you've use for 4x10, but instead do 8x5, with less rest (say 30-60s). There's studies that show when volume is equated, growth will be the same anyway. BUT when staying further away from failure, power and strength goes up. Plus, because you'll avoid that fatigue that can lead to injury/crappy sessions. I've done this with 8x5 and then 10x4, slowly upping weight. The reality is for BJJ there are so many ways to work it, but for me this ticks a lot of boxes. Depending on how intense/frequent your bjj is would dictate how often you lift, which probably has a bigger bearing on injury/fatigue than any of these specifics