code: func (c *MConnection) CanSend(chID byte) bool {
  	if !c.IsRunning() {
  		return false
  	}
  
  	channel, ok := c.channelsIdx[chID]
  	if !ok {
  		log.Error(cmn.Fmt("Unknown channel %X", chID))
  		return false
  	}
  	return channel.canSend()
  }
docs: // CanSend returns true if you can send more data onto the chID, false
  // otherwise. Use only as a heuristic.