Yes, old dogs can learn new things

I'm currently babysitting this cute little guy. He has a lot of issues so I'm having to be with him 24/7. I know a lot of those issues have to do with his past and present owners but he was a rescue at an older age so who knows what he's life was like before. 

Anyways, Romeo is normally walked with a retractable leash. I think these type of leashes should be illegal! Because of that Romeo isn't really leash trained making it difficult to take him anywhere.  During our first meeting, I absolutely refused to use an extendable leash. I said he would be kept on a short leash, learn to walk next to me and at my pace. It's really for his own safety and for anyone else walking near by. I've seen way too many people tripping over the extended leashes or the owners have no idea their dog is doing behind them.

He also has major separation anxiety which I'm also working on but that's really more about retraining the owner. He's doing great with me but I still can't leave him alone.