Not to beat a dead horse with dogs...
I entertain the following, which gives rise to my speculating about plans vs. no plans and perp identity : 1)provision to ensure dogs would not gain neighbors' attention was made 2) dogs attended to by someone known to the dogs (could be owner) 3) dog's circumstances such that no need to consider them a "threat" (i.e. that their behavior might draw a neighbor to investigate, call ACC, get the lawn crew poking about). Could be doggie door led to area apart from the action--utility or laundry room where food placed and then they sheltered inside as per usual and went back out in the a.m.
On the other hand, dogs were kept in back of house IIRC, and that back space could be such that dogs would not be seen or heard, a fact that would be obvious without need to case or to know (prior) their temperament and routine.
Still, IF #1 or #3 the case, implies prior knowledge or observation. JMO perps knew prior that no need to disable dogs. Perhaps benefit in dogs frolicking outside as usual in a.m. to give impression nothing amiss.
I concede an on-the-spot observation might have indicated to perps that dogs not an issue, their behavior moot.
#2 is the usual thinking: an accomplice familiar with dogs tended to them.
OR dogs had access to a guardian without him or her being seen by outsiders. No duct tape, bindings, threatening "other" while guardian interacted though. Otherwise dogs could get agitated and bark loudly enough to be heard by passerby.
Or is it that the house is hedged, set back far enough, insulated well enough from outsiders that sound not an issue?
JMO Dogs drugged, dogs most laid back dogs ever, provisions made, prior knowledge of dogs, or perp/s know how to read and handle dogs in general , or perp/s so dog crazy would rather risk discovery than harm dogs in pre-emptive strike.
I tend to think NG, though mis-identified "Ginger" as vicious guarder, she was right that perps had to have prior knowledge through casing or through insider info. I think she meant that dogs are protective, would bark if they felt threatened or felt guardians were, and that they would react to strangers, invasion, the "unusual" in some way so as to draw attention unless perp/s had factored them in to the equation, knew how to deal with them, what time dogs out of earshot, out of the house, their day to day routine.
I don't know THESE dogs, but I do know dogs in general as a dog trainer and long-time kennel attendant and dog volunteer. Friendly dogs who approach anyone and everyone react to changes in routine, bark when left outside over night, scratch at doors when they expect to see guardians and don't, sense danger, hear glass breaking, see people carrying stuff in and out of a house and get curious...
JMO not drugged as kept to usual morning routine outdoors as attested to by lawn crew and neighbors IIRC.