partially yes - but this would bring us close to a policy violation and potential blocking. user streams should only be access from a twitter client app (mobile/desktop/web) but explicitely not in a server-to-server type of scenario (see docs). as soon as a lot of our major users are being hooked into the user stream mechanism, we may experience IP blocks or policy related shutdowns. it's a scary thing, they have all that power and we try really hard to stick to the rules here.