Thanks for the feedback. Maybe not what I wanted to hear but perhaps what I needed to hear.
When I said I was feeling strong, I mostly meant I was feeling my body was absorbing the load, I was sleeping well and while the legs felt tired, they refreshed after an easy day.
I guess the weird part for me is that all the symptoms (dead legs, low energy, poor sleep), suddenly appeared during the recovery week, when I was drastically reducing my training load. They were not really there during the training block. Is that a normal part of recovery or a sign I pushed too hard?
I went on a longerish run on Saturday (as part of the plan, 40% of the weekly volume, which was 50% reduced volume of the week before) and felt really good again and fresh.