While I have no idea to which Freeper you are referring, I would imagine the reason is that for Baptists, as well as Calvinists, baptism itself is not salvific in any way. IOW, it has no where near the importance that Apostolics place on it. Therefore, it would not be a "compromise of faith" to go from Baptist to standard Reformed.
One difference between Bible-believing Protestant churches and Apostolic churches is a matter of freedom. Either the Holy Spirit is free to lead as He sees fit, or He is shackled under the authority of a particular group of men. I might add that for you and Mark, you disagree on which group of men should be followed. If following men first was proper, how could any of the rest of us know which group of your men was right?
That is a straw man, FK. Ptotestants will pray with anyone, whether they share their beliefs or not. That is the kind relativism that puts any absolute truth about God into question. It says that everyone knows a little bit of the truth and that the truth is not known to anyone.
The Apostolic Church knew the truth from the beginning as handed down to this Apostles by our Lord Himself. There can be no relativism in it. Again, the path is narrow and there is no room for heresy. To Protestants, the path is wide; it's a pot shot.