14
Yes, the DTD shows that it is allowed.
<!ELEMENT table
(caption?, (col*|colgroup*), thead?, tfoot?, (tbody+|tr+))>
The DTD also has a comment which explains why:
Use multiple tbody sections when rules are needed between groups of table rows.
I copy pasted your title in google and the first link is : http://www.w3.org/TR/html401/struct/tables.html#h-11.2.3 ,
"Table rows may be grouped into a table head, table foot, and one or more table body sections",
so yes you can !