lets start with one point-all pump and dump groups are basically shady,thieving instruments designed to
make one (or a group of the fastest guys) guy make money,as per some weird coincedence it is the admin of the group
the rest will always lose money,the laws of physics work in trading too-you can't get something without someone somewhere losing
so in this case the ones who are losing -the members of the group,again bar the shrewdest and the fastest ones
I don't even want to talk about the damage they do to the coins
some of which would never recover from the dump
There may be cases like that but it's up to the investors that pumps and dumps after which it recovers but not that fast of course. If you are not in a hurry or others are not too then you may fit in. That is really testing someone's patience to earn. As for me, no matter what I am into this group and I feel good because everyday is a new lesson for me about bitcoin and I need to polish my ideas because I hope for a good future someday.