When leading against a suit contract, should you consider leading short suits (singletons or doubletons)? The great Italian star, Benito Garozzo advocated: "When in doubt, lead a singleton."
I've found this to be great advice. However, here are a few exceptions:
1) Not a singleton trump--we are talking about side-suit singletons.
2) Not singleton Kings--too dangerous. Other singleton honors are okay to lead.
3) Not when you have a better alternative (like maybe KQJ or partner's suit).
4) Not when you don't want a ruff. For example, you have QJ10 of trumps.
5) Not when your trump holding indicates a "forcing" defense. Such as A10xx in trumps and QJ109x in another suit (try to make declarer ruff and get trump control).
What about doubletons? Not doubleton honors (Ax, Kx, Qx and Jx are dangerous--not recommended in general). Other doubletons are "okay." If you have nothing better to lead, choosing a spade from say, two small ones, is not a bad idea. It is safer than leading from an honor and sometimes it might lead to you getting a ruff. It is even more attractive if you have a trump control (like the ace).