Let's say I come across a method like this :
def do_upload(pagename, request):
...
Here I can guess from the context that it's a http request, so let's say I want to get the date header and print it in W3CDTF format. If it was typed, then I'd simply look in the documentation for that type (class). But how do I find out what methods 'request' supports?
hmm. We don't have that problem in Smalltalk. We have tools that can find implementors and senders of methods for us instantly - so it's an utter non-issue. The type information adds nothing of value in that regard. I'd suggest downloading a Smalltalk implementation and taking a look - you'll see why it's not a problem.