Answering 'honestly' is noble, but it's not enough. Similarly - being conscious of 'Health and safety' is important - but it's not enough on it's own. Also in a way, consulting a "train driver of many years" might go against you. They'll be from a bygone era when things were different. A lot of the old hands where I work have laughed and admitted they'd never get a sniff these days at the job because it's changed so much. Whilst I don't doubt your friend or associate has earnt his job as driver: he might not necessarily have the wisdom to interpret a modern day application form: they're very clinical.
I don't think there's a sure-fire way to get enough "points" to gaurantee a pass at application stage - regardless of how many times you re-word it. I suspect comes down to what skills you have gained through experience in life - and how these prove you can become a good driver. Most industries use these - and sometimes they're referred to as 'core competencies'. They include things like 'composure in an emergency', concentrating for long periods of time, following a lot of strict rules and procedures in the workplace, teamworking, problem solving etc to name but a few. Then there are other factors which can determine how someone sat in a HR office reading your application feels about putting it in which of the two piles: your spelling and grammar, previous occupation (safety critical?), age (too young and inexperienced, or nearing retirement age), distance from depot, and general how you put yourself accross as a person.
It is a tough nut to crack - and you might not be falling short anywhere: it could be the calibre of a few of the other hundreds maybe thousands of applicants pip you to the post. All you can do is keep trying, and perhaps if it means that much: undertake something in life that'll give you the opportunity to exhibit these sought after experiences and skills. Some will suggest 'getting a foot in the door' on the railways via another role.
I see you live in Redbridge. Have you considered a job on the London Underground? They regularly recruit hundreds of platform staff, and after a short time in that role you can apply for train operator jobs. From there you could apply to the mainline in another couple of years. Just a thought.
Best of Luck