Yes. After my discharge from residential treatment (9 months, weekend leave every weekend) for youths, I spent about 3 months in day treatment at the same facility. It was fairly useless. I'd arrive at 8.00, have a cup of tea, walk to the school that was on the grounds that started at 8.30, have school until 14.00, walk back, go to my room (I was the only day patient that had a bedroom, as I really needed a place to 'calm down') to rest. At 15.00 there was tea time, after everyone had finished their tea we all discussed our 'week goal'. Then I usually spent time reading or talking to the other youths. I'd go home at 16.30.
Once a week I'd see my individual T and I saw my pdoc regularly (once a week or every other week, I think. That was unusual - most only saw him once a month).

I think it can be really useful if you have group therapy and stuff, but this was mostly going to school and resting.

Residential was the same, by the way - my facility actually had 2 groups (or programs, or whatever you call it), group A, one of 9 persons in day treatment and group B, one of 7-9 persons in residential and 0-2 persons in day treatment (so both had 9 persons). Usually when you left residential and continued day treatment you went to group A, but I was one of those that stayed in group B.
Anyway, residential also didn't have group therapies besides discussing your weekly goal every day, but if you needed help during the evenings and such you could just go downstairs and ask the nurses.
The school vacations were actually the most useful - then we did have group therapies and workshops.