HTML4 Tables: row groups

I have several questions regarding row groups, which I could not find
answers to in the HTML 4 spec. Viewing document on the topic made me
even more confused, and brought up more questions.
Could someone please enlighten me?

(Without using "rowspan=0")
- Can a table cell span multiple TBODYs?
- Can a table cell span THEAD and into a TBODY?
- Can a table cell span THEAD into TFOOT?
    If so,
        - Would "rowspan=2" in a THEAD cell span
           into TFOOT or TBODY?
        - Would a cell spanning through THEAD and
           TFOOT span the whole table or split
           between the THEAD and TFOOT?
            - If it were to split, where?

- If a table cell cannot span multiple row groups,
    would the rowspan be ignored or would empty
    rows be added in?

- I assume that if a table cell spans multiple
   rows/row groups, it inherits properties from
   its row of origin (location of cell tags).
   Is this correct?

My thanks for your time. ^^