Yes, yes and yes. Interesting read today. Those that have not added resistance training or weight lifting early during the base season, will find that those that have hit the gym are ahead of them, IMO.
I have seen my efficiency and power output on the bike increase dramatically since I started going to the gym 3-4 times/week. High reps is the key. I chatted with a friend about functional weight lifting, which makes sense to me. Do not do leg extensions, instead do full body squats or power lifts. Sitting down to do curls is not only monotonous but it is not functional... pull-ups are better and the list goes on.