I have heard that the worms will reproduce better when the population is dense all other things being equal. They can find each other better when they are not all spread out. I don't know if crowding them will help much in the short term though. It takes a while for the offspring to get big enough to help much in the eating.

the only time worms will for sure produce the max cocoons is when conditions are poor, like getting too dry or wet or cold or hot - they preserve their population by leaving cocoons to hatch out when conditions improve - otherwise they breed as fast as they become sexually mature, and have the inclination, which will occur regularly if they have good conditions [lots of food and correct moisture/temperature levels], but it can take up to 3 months for a new hatchling to reach breeding size, "crowding" is likely to produce slower population increase because there won't be good conditions

patience grasshopper, you can't force the situation, just feed as much as they'll use [about 1/2# per # of worms/day] and take what ya get!!

Bill