I keep reading here posts by people who denigrate their accountants because they don't like what they heard from their accountants.
Your type of questions is fairly simple, fairly basic, not complicated at all. Any accountant who has been in public for some years will have the answers for you. Here, I am referring to accountants who either have their own public practice or someone who works for someone in a public practice.
These days, accounting is a multi-discipline profession. You need to ask an accountant who works in the area of your query.
Your "normal tax accountant", is he someone you see only once a year, may be for just 30 minutes, when you go to him to prepare your tax return ? If that is the case, he is unlikely to be familiar with your situation re trading, you need to have a proper face to face consultation with him.
So, you think his advice to you "does not sound right" ? If you know more than he does, why do you need his advice ?