BTW turtleboy, big fan of your work! No disrespect intended in the above comment.
None taken, it's fine. But I think your argument is with the viewer rather than the model or creator of the content. As you say, people may seek out mother/daughter fantasies and that's on them. Others are obviously turned off by that concept and can choose not to watch but that doesn't make the participants wrong or indecent. The only problem is when people judge the model's behaviour as somehow obscene, based on their own sexual feelings.
If a mother and daughter feel the fetish is harmless then it is harmless to them and incest doesn't come into the equation, even if it exists in the mind of a specific viewer. At the end of the day, they're not doing a jerk-off-instruction video and they're not saying they want you to play with yourself when you watch - generally, they'd prefer not to know. Remember that everything is a fetish to someone. For example, many women like wearing sexy heels and continue to do so even though it is common knowledge that some (possibly many) guys will go away and fantasise over that. It is possible to know that something is a turn-on and at the same time, to not want to know about it.
The same thing applies to models in tickling videos generally. It's safe to say that more than 99% of the models do not have any kind of tickle fetish in the slightest. Some will try to understand it and may find it interesting, others won't care at all. In my experience, virtually none of them feel they are doing anything sexual however (unless it's a more adult scene), even though they know it is watched by people with a fetish. To them it isn't porn, but to the viewer it often is.
I'm not disagreeing with you on any of that. I think I said at some point that I fully think most tickling videos that don't involve overt sexual content aren't sexual in any way for the models. I'm sure it's nothing more than a job and/or a fun shoot of an activity that's otherwise harmless. You and I are in full agreement here that the incest fantasy is only on the part of the viewer, and the models (unless they also have that particular fetish/fantasy) are in no way involved with that. I just personally think that, regardless of what the models think or do, what is being created is inherently an incest fantasy video. If it wasn't then there's no need to include the information that it is a mother/daughter, especially if they aren't actually related. The video being created is objectively a fetish video, it's intended to be a fetish video, it's using either actual family members or actors who are implied to be family members, and what they're doing - even if it's completely innocent on their part - is done with express intent to create sexual arousal in the person watching family members tickle each other. The models themselves aren't incestuous, but the content created is intended to fulfill an incest fantasy.
Again, I don't think there's anything inherently wrong with it, no one is getting hurt, everyone is on board, it's pretty harmless, and I'm sure a lot of the models have a great time making them. It's just not for me because of the implied incest component.
I'd agree with most of what you say. One part I would disagree with is the intent to create sexual arousal - the models really don't care whether someone gets turned on or plays with themselves watching the video. They'd mostly rather not know, they're there to do a job and it's a fun job. Similarly, most straight models in F/F clips don't consider that they are doing lesbian scenes or performing to turn someone on...they're just having a laugh and getting paid. That said, some clips/producers require more roleplay where models are acting up for the viewer, so I'm only speaking for my own way of shooting here.
The only other thing to say is that I think the assumption of incest as the appeal of these videos, is actually not correct. I.e. I don't feel that people tend to watch mother/daughter tickle videos because they fantasise about mothers and daughters sexually. The appeal comes from a number of factors - tickle fantasies involving a mature woman and a younger woman, the authority figure of the mother being tickled by the rebellious daughter (similar to the teacher/student fantasy). Also, family relationships involve a shared history and a sense of realism that isn't always there with two random models. The idea that these people know each other well, know one another's weaknesses, enjoy getting an opportunity to playfully tease, punish or bully one another, revenge for past grievances....these are all bigger factors in the appeal of these videos. Actual 'incest' I think has little to do with the fantasy for most viewers.