It really won't stop as long as you have a brooder that opens from the top. Guineas are great at looking up and seeing hawks, and your hand coming down at them has a similar effect. This is one of the reason I don't use brooders that are accessed from the top.
With my original guinea flock of 30 keets, I had a large "brooder" area (my enclosed front porch) so I was able to sit on the ground in the midst of them and get them to come up to my hand for treats. The four remaining adults (now 11 months old) do not run from me but they certainly aren't going to come running up to me and jumping on me, which is okay with me. Those keets are the only birds I tried to befriend with food. I no longer use food as a taming tool because begging birds annoy me, and my recently killed turkey (that was hand raised by people other than me) use to nip at my fingers looking for grapes and treats, which was annoying.
Starting from day one, I sit with my birds several times throughout the day for a few minutes at a time (5-15 usually). I just watch them and I become part of the scenery, nothing special. Occasionally I pick them up, and as soon as they stop struggling I let go. Very quickly they learn there is no point in struggling because nothing bad is going to happen and they are free to leave when they want.
So far, I have had the best results with two guineas that I have that hatched and were brooded with two turkeys. They are all a month old at this point, and all will come to me and sit in my lap, especially in the evening as bedtime approaches. With a large group of keets this is near impossible, because they spaz out and get everyone else riled up.
Anyway, my first recommendation, which will likely have the greatest effect, is to change brooder setups. If you can move them outside, even better. I move them outside by 2 weeks (well, now 2 days since I just finished my outdoor brooder setup).
