I know it's a difficult profession, but are you wanting to jump back in?
In a heartbeat.
I suppose it can be difficult. But 'difficulty' doesn't feel 'difficult' when it's your own gig. I do not know Colin (who started this thread) but my guess is that there are days that are more trying than others, employees and the odd customer that can be exasperating, and probably some other 'issues' but I would imagine that if you asked him--or Konrad--if there was another placed he'd rather be he'd say no.
If I am not juggling new recipe ideas in my head I'm working on restaurant concepts--I have six, fully-formed, in my head. If people here or from other forums ask my opinion I am very happy to offer it because it is what I enjoy doing the most. I particularly like the people on this forum because they are so positive, willing to share, and willing (and wanting) to plug away at something they enjoy (cooking Q) to get it 'right'. I am amazed, and sometimes saddened, by how negative some of the people in the forums for professionals can be; how cavalier.
The concept I have that I'd call the barbecue one (more like barbecue writ large) is one of countless approaches countless people could take. I think that those people here that are interested in pursuing a dream of starting a restaurant, joint, catering gig--whatever--should take the steps and make the motions and gather the info, refining or adjusting the dream along the way, till they're ready to make the step. Start small, and grow; start small and keep small; go large out the gate; it's all up to the individual and there are many possibilities. Gather info, ask questions; explore, then decide. There is much more to it than cooking. (Listen to the people who challenge your assumptions, it'll help you refine your ideas. Avoid those that just seek to shoot you down.) But without waxing rhapsodic or getting too existential here, I have known too many people who have given up on a dream before even taking one tiny step in that direction, and as the years pass regret it more and more.
Any venture (food service or otherwise) can be difficult, daunting, trying, exciting, exhilarating, rewarding. Jump in again? You betcha.