"My pullups are at 12 these days. I think with pullups every pound of bodyweight counts, I am lifting weights too and bulked up to 200#. When I was younger I was smoker and superslim so I am questioning if pullups is true measure of anything. If you cannot do even one then I think all you need is to cut some 10-15# - very doable. You may be surprised with results. Same with running speed and indurance, as you drop bodyweight you run faster and faster while your strength goes down the toilets. That's why I personally not very concerned about my time on 1.5 miles anymore."(Weiss, army.ca)
The way I understand it, pull-ups are a function of complete body fitness. If you are strong through the abdominals, your ability to stabilize your body and move through the range of motion smoothly should go up. That means you need less energy to perform your reps and lets your back and arms do the work they should be doing. Your back is a massive player in this motion, it hits your traps, your lats, your deltoids, and your pec's.
The final pull to get your head over the bar can be helped along by having strong biceps that pull you that last little bit.
If you are having trouble performing one rep, negative training is one good place to start. Or you can go for fitness and use the machines in your gym to build that fitness (the ability to perform an action in large numbers) in all the muscles you need to use.
Use the pull down machines and build your lat pulldown weights to hit your lats and traps. Seated cable rows to hit your chest and back. Shoulder raises/french press to hit your triceps, deltoids, and smaller rotator cuff movers. Captains chair/Dips for the abdominals and other stabilizers.
Regardless of weight, as your fitness goes up your ability to perform will go up as long as you don't injure yourself. Before anyone gets bent out of shape yes, your weight will/should fluctuate unless your already highly trained. Just like running if you focus on cardio and not on strength then strength will go down and vice versa. If you focus on hypertrophic strength training (meant to only grow big oxygen hungry muscles) with high weights and low reps your cardio will go down the toilet. Balance and knowing what end goal you are aimed for is the important thing.
Push-ups hit alot of the same muscle groups as pull-ups only to a lesser degree and can help increase your overall body fitness. As a result push-ups and pull-ups complement each other well. Just like the push-up the pull-up is a combination of a lot of strengths coming together at one time. A kinetic chain where every little step counts and adds up.
Popnfrsh it was good to see you are taking a training break to let your muscles recover and to focus on other important fitness areas. If you saw improvement in your peak reps you must be doing something right. If you go to a gym with a fitness trainer on staff you should ask them to help you design a program for strength/endurance not hypertrophy, they should be able to help you improve in a lot of areas at once. Good luck with your training.
By the way, what is the total number of push ups you can do in a day now?