Another technique I have found works well for myself and others is to have all players in the group repeat a main pattern together every once in a while to reinforce the songs main line and to help keep the rhythm. This can be done by most of the players repeating the same notes with the same timing for a bar or two. I also can be done by having those who are soloing play the same notes, hit and hold the root of the chord or the chord itself. This can keep the solo from staying too far from the main line in the song and also make it smoother for the listeners. I often find that if at least the BASS and soloing instrument do this together it works well. Give it a try and see how it works for you. Add your comments on this or similar techniques you have used.