Hello,
You can’t "lazy-pull through the transcoder", you can only lazy-pull directly from a source. However, you can transcode the stream after it has been pulled. If you issue a transcoder command to use the stream that will be pulled, it will start that transcoding job once that stream is available. Do be advised though that this will cause some incremental performance hits because the transcoder will be started periodically to test if the source stream is available yet!
Bryan