There was a caker on here a few years ago who took something like 14 hours to make a pirate ship cake. It was awesome. She was transitioning from home to an employee in a bakery. However I think she got fired or asked to leave because a bakery cannot afford to loose money like that on sucha slow decorator. Even in the chichifoofoo shops they might be more limitless in design--I know one girl got to do a large oil well that spewed chocolate--but they know how to determine the hours of work necessary and therefore how to bill for those work hours.
So speed is crucial. There's no way around it.
Another friend of mine could not believe how physical cake deco is. Back breaking, foot swelling, leg aching, arm burning hard labor.
As to how you should word your resume, hmm, perhaps acknowledge that you are looking forward to learning how a full time bakeshop works or something to that effect. Maybe start out in a position icing cakes and work up or offer to. Just give a bit of a nod to not being fully skilled.
A home decorator is both over qualified and under qualified so in your resume you want to give a nod to bridging that gap. It's like a home decorator just hatched out of a beautifully decorated sugar egg. They look like a cake decorator and talk like one but they can't walk/work like one yet. They're a snow globe the bakery would set on their shelf.
There's a genuine rift between bakery owners and home decorators & vice versa. Bakery owners are upset that home decorators can't function successfully in their world. Home decorators think they are better than bakeries who have been churning it out day in day out because they do not have the luxury of time that home cakers have You want to gently softly that in your resume even in a high end cake shop/bakery.
I'll be upfront: I've been working in supermarket bakeries in every capacity for a very long time. I've also worked for a couple of wholesale bakeries specializing in weddings as well as occasionally doing cakes on the side at home. In other words, I've see all sides of the OP's question, and there is a lot of truth in the "snow globe" effect: You can talk the talk, but you have absolutely no idea what it's like doing cakes for 8 hours a day, 5 days a week, or even longer, in a commercial setting.
Two chains I worked for refused to hire home decorators because of the time and money that would be spent bringing them up to production speed. These two chains churned out a lot of what some may call "crap cakes" for the display case, but those "crap cakes" demanded some finesse in a timely manner because the customers would pay accordingly for the finesse. Whenever a holiday or graduation rolled around, we were inundated. There was no way we could spend hours on one particular cake, so a decorator who was quick AND creative was worth his/her weight in gold to us. Sadly, they were far and few between.
I broke into this business OTJ. I started as a clerk. The more I observed, the more I wanted to learn, so I was always asking questions like, "How do you do X?" or "Can I watch you do Y?" Little by little I learned how to do simple cake-ing like icing, making half roses, different borders, etc. I eventually graduated to doing decos, then, as my skills grew, I was given the occasional special order cake. At the same time I learned how to finesse by making the display case cakes. It didn't happen overnight, but I stuck with it. I read anything I could get my hands on concerning decorating, My first boss let me bring home parchment bags, icing, and cardboard rounds so I could practice. In other words, enthusiasm and genuine interest is everything :)