In case it’s of benefit to new users or those trying to decide when to use subtasks…
@Ben_Brenner and @Bastien_Siebman, I disagree. Whether or not to use subtasks has nothing to do with how many of them you might have but rather how you need to use them.
They’re excellent at providing progressive disclosure – not cluttering the main task list. They’re excellent for breaking down a task’s component parts, or enumerating anything – I use subsections and subtasks instead of Description often because the ease of subheadings, reordering, and marking complete is much better than trying to manipulate such things in the Description. (But I use Description often too in all other cases.) They wrap so you can always see full content no matter how long the subtask text is. And if you need no more than assignment, due date, and complete/incomplete, they’re great. I freely use tasks with dozens of subtasks when appropriate; my projects are shorter and simpler for it.
I would not use subtasks for most everything else (except what I’ve forgotten here! haven’t really vetted the above as covering every desirable use case of subtasks). In other words, except in special circumstances, I’d avoid having to descend into the subtask to see a comment thread or anything else including multi-homing.
A common best practice I recommend with subtasks is to use the task’s comment thread (not the individual subtasks’ comment threads) to discuss the task or any subtasks, using an @reference to the subtask for context. This avoids descending into the subtask but still gain their benefits as outlined above.
On the other topic here, I still have a couple of things Ecco Pro which runs fine in Windows 10–amazing product, especially for its day.
Larry