Drop sets are a good alternative to a training partner and essentially serve the same purpose. A training partner is there to help you do those extra 5 reps when you couldn’t possibly do more by yourself. With drop sets you do as many reps as you can, immediately lower the weight and continue.
When you have ceased making progress and are getting frustrated, drop sets may be just the thing to get you to the next level. What drop sets allow you to do is to train more intensely which will mean you will need more rest between sets and you will need to keep your workout short (under an hour). When I train, I do at least one third of the sets in my workout with drops sets. Drop sets take a lot of both physical and emotional energy. Whether we are lifting heavy or light, drop sets are the same. After lifting to failure on a set, we immediately jump up, decrease the weight by about 40%, and do as many reps as we can – this takes incredible focus. Don’t just choose an arbitrary number of reps you will do, do as many as you possibly can while keeping perfect form. If you didn’t do at least 6 reps with good form then next time try dropping by 50% so you can. Now take a well deserved break.