Trimming flower stage

"need" is wrong word for sure. This depends on understanding typical growth after this point or what you expect in flower etc... you'll learn how deep to expect high quality buds and where the zone of larf starts. This doesn't really impact yield too much and probably slightly reduces it if anything. you can always remove axilla (branches) and not take off the fan leaf at base with it. Same with undeveloped axillary buds - remove them but don't remove the leaves unless you have to. leaves are everything... storage, solar panels, production zones, lungs... extremely important and you should have an excellent reason to remove them. it should be rare or due to the plant sucking one down to shed it. the plant will shed excess leaves on its own. don't try to be smarter than the plant on that. stunted? runt? just a stocky plant? hard to know for sure. the other plants growing fine can help eliminate possibilities. If you have too much branching in an area, thin it out. If you are 1 week into flower, you have 3 more weeks of solid vege growth before it tails off. Consider wwhat it'll look like in 3 weeks not 'right now' -- what is worthwhiel to keep? what can be trained? what will just be a clogged up pile of plant mass waiting for a pathogen to come by and set up shop? try to be systematic and spread out any pruning evenly as possible - with similar number of mouths to feed per branch etc...