On Friday, September 26, 2014 1:55:04 PM UTC-4, la gleki wrote:
practice shows that tanru remain vague and dont lead to any idioms.
It's a bit early for that. Wait til you have thousands upon thousands of daily speakers. If it is possible it will happen. Right now it might be a bit blue moon (idiom intended), at least for the really obvious kind. But there's probably already a bit more idiom going on then anyone realizes by imitation of native phrases. For example "fagri jaurflevau".