Adding here is a friendly contribution I received via PM (I will credit the AUTHOR if he wants it - I will check in the morning) - I reproduce it here so you can see that there is more to 'internal' politics than first meets the eye.
"I think you need to put in some background explanation here, so we can understand what you are talking about. It's not clear whether you mean: (i) one or two people leaving Class War, and joining another existing anarchist/revolutionary group or (ii) Creating two separate groupings or worse still, and more confusingly two separate Class Wars (like the short-lived Class War Organisation (CWO)).
Whilst there is no point people staying with a group if they are deeply unhappy with its aims, methods, structure and personel, splits of the second type rarely if ever do any not good. They are often over personal animosity rather than substantive political differences, dilute resources -- financial, personal and emotional -- and lead to confusion (the CWO example again).
Of course new groupings can work in alliance with older ones, but that requires an non-acriminous departure. Radical groupings have always been at the most effective when working collegially with others. J18 being a prime example, they are least effective when they try to dominate or go-it-alone. So if you do split, you'll need to work out how will you work with those you have left behind, who else will you be struggling alongside. Are you going to create yet another separate organisation or join an existing grouping whose politics are similar to yours?
... it seems likely that a parting of the ways would be most beneficial for all concerned. I hope you are thinking of how you can best meet your radical desires beyond CW without interfering with the efforts of your former comrades and friends."