Should you move for leave of court before using modes of discovery?

[1] Depositions (whether by oral examination or written interrogatories) under Rule 24. This is before action or pending appeal;
[2] Interrogatories to parties under Rule 25; and
[3] Requests for admission under Rule 26.
Under the Rules of Court, leave of court is NOT necessary to avail of the aforementioned modes of discovery after an answer to the complaint has been served. It is only when an answer has not yet been filed (but after jurisdiction has been obtained over the defendant or property subject of the action) that prior leave of court is needed, the reason being that at that time the issues are not yet joined and the disputed facts are not clear.