I read your article about dog parks and completely agree, do you have the same feeling about doggy daycare

I do have the same feelings about most Doggy Daycares and in some ways they are worse. The problem with the daycare is that you aren't there, so there is no way to know what may have happened while your dog was there. A daycare is also only as good as the staff and my best guess is that many daycare employees are not as well versed in canine body language and signals as they should be.

It may be fine but it only takes one negative experience to forever change a dog's attitude and world view. I would be especially cautious with any working or herding breeds that are not typically dogs that enjoy dogs from outside their family or circle of friends. German Shepherds, Malinois, Akitas, Rottweilers, etc don't typically enjoy being in close proximity to dogs they don't know especially once they hit mental and sexual maturity. Of course, there are exceptions to every rule but you will have to decide if the potential benefits would outweigh the risks.

I only "socialize" my dogs around other dogs in a controlled setting like a class where all the dogs are under the control of their owner/trainer. Your dog has shown no aggression to dogs and that's great, sometimes putting them in a dog park or daycare can change all of that in a short time. I personally would not take any of my dogs to either a dog park or daycare.