Can I use developing as an adjective, in reference to something that has developed something else? That is, if I say "It was a developing experience", does it work in the sense 'the experience developed me', or is the only possible (although somewhat forced) interpretation the intransitive participle one – that is: that it was the experience that developed, not me?
If it is indeed possible to use developing in the adjective sense, what intensifier goes with it? "It was a very developing experience" sounds dead odd to my ears, whereas "it was a highly developing experience" sounds slightly better (though still odd – which, of course, only supports my suspicion that developing can't be used as an adjective, but rather only as an intransitive participle).
And finally: if developing cannot be used in this way, what word could I use instead? I realise I can just paraphrase, but is there another word I can use as a premodifying adjective?
As always, I'd be very grateful for any help I could get!