Zelandakh, on 2016-March-11, 10:17, said:
I think that is reading too much in "a small spade". If West led the normal 4 from 42, I can easily see that declarer thinks that it is from a four or five card suit.
But, as Hrothgar pointed out, leading a short suit with a weak hand and a long suit with a strong hand is an encrypted lead, according to the definition.
There are more situations where every expert will play signals that are encrypted - according to the definition - simply because the "default" signal won't help partner and partner can see that the default signal won't help him. In some situations, the key will be available to declarer and in some it won't.
To me it seems very difficult to make a good definition that properly describes what the regulators want.
Rik