Bob, we gotta find you some better reading material.
Not only, as Ann pointed out, the author not exactly accurate about the Calvin/Severtus event, but he's not very accurate about the roots of Baptists either. He implies that AnaBaptists later became Baptists, but that is not the case. Today's Anabaptists are the Amish and Menonites, not us.
A fairly good link that I've found to be accurate so far:
http://www.christian-history.org/index.html
The info on there might not be totally correct in every instance (I haven't read the whole site), but its a good jumping off point for learning church history.
About the only thing the author in your link treats accurately are the 5 points of C/A and even then both are treated very simplistically. The rest is one sided opinion and not very scholarly at all. Indeed, it seems he wished to define the term "baptist" in his own terms, seperate and apart from the rest of church/religious history. Only his definition leaves a lot to be desired.
For all you Cals reading, the guy insults us so-called Arminians just as badly as he does you later on in the article!
Do a google book search on both men. You will find a good portion of both men's works out there in the public domain. Not exactly easy to read some of the translations (they date from the late 1800's to early 1900's) but you can find info that is much closer to the horse's mouth than the site you posted. You'll also find some good suggestions on more up to date books that you can purchase. (though you'll want to be watchful of the author's bias', but one must be careful of that in any "religious" book)