You've posed an interesting question, France.
One reason that <dl> has a <dlentry> wrapper is specifically to bind a term to its definition, unlike the HTML model of a definition list, which has no such grouping. However, the <ol> model (upon which <steps> is based) has a simple model of one or more list items, with no other grouping. It was never clear that there might be a need for something to group list items other than to show hierarchy. The same consideration could be asked of any base element that has some inherent internal model: do we need to express just the information model itself, or do we also need to anticipate containment that exists only to manage portions of a model without being part of that model? In DTD-based systems, you can do that with good old general entity declarations:
<!ENTITY mygroup1 "<step>Run</step><step>Jump</step>">
...
<steps>
&mygroup1;
<step>Hide</step>
</steps>
However, this level of containment reflects reuse based on a virtual storage artifact outside of the DITA architecture (and specific to DTDs). Rather than calling on DITA to solve this problem, this might be a particular use-case for using XInclude or XLink outside of the DITA architecture itself.
But to argue against myself here, I would also suggest that in a truly componentized view of the steps, "Run" and "Jump" would each be independent and would be referenced individually rather than as a set, meaning that the solution might lie in how you refactor the problem.
<steps id="run-jump-hide">
<step conref="runstep"/>
<step conref="jumpstep"/>
<step id="hidestep">Hide</step> <!-- Hide is separately reusable elsewhere -->
</steps>
In this scenario, the first two steps are now reusable individually or in different sequences without having to create new definitions for the alternate appearances. And its containing <steps> can be reused wherever this particular sequence happens to repeat.
Regards,
--
Don Day <>
Chair, OASIS DITA Technical Committee
IBM Lead DITA Architect
11501 Burnet Rd., MS 9037D018, Austin TX 78758
Ph. 512-838-8550 (T/L 678-8550)
"Where is the wisdom we have lost in knowledge?
Where is the knowledge we have lost in information?"
--T.S. Eliot
