Ok, so it seems I am making humungous strength gains in my legs every week. I can up the weight on the barbell by 2.5kg (approx 5lb) every week. This past week I even upped it by 7.5 since I accidentally put 5kg plates on the bar instead of 2.5s

So my musing is this. If I can increase the weights on my squats so much each week, but the decrease of the weight I use for assisted pull ups/dips (and thus increasing load on muscles) goes up about 5kg on the machine every 3 or 4 weeks.

then

the amount of weight increase every week is proportional to muscle size? So I can lift 2.5kg more every week with my legs and say the amount of muscle worked during a squat is twice that used in an assisted dip, then can I only increase 1.25kg every week using my back/arms?

Does that make sense?

I did originally think that I could go up by 2.5kg every week, because it was such a small proportion of the complete weight that I was lifting, I think this makes more sense....