I'd used London's Oyster for years so had the general gist. Buy it, tap it, switch modes at will, fess up if you breach your zone, top up as you go. How hard can it be? Pretty hard, turns out. First hurdle, purchase. In London it's easy. All tube stations sell both cards and top-up, via both machine and ticket-booth. Opal, by contrast, is available only at selected stations. Which stations is for them to know, and you to find out. There are 1170 designated outlets across NSW. But there's nothing intuitive or in principle about the selection. Almost all the outlets are newsagents, gas stations or supermarkets – but it's not all gas stations or even all BP stations, much less all rail stations. A search for Redfern and Town Hall stations produces no results. This spotty and counter-intuitive selection is not a passing glitch. It's not teething, to be resolved on "roll-out". It's permanent. The department says it has no plans to allow Opal sales or top-ups at all stations. It's as though the question itself is unreasonable. Sell train tickets at train stations? Uh, why?

Given that stations will soon cease selling paper tickets – sales of many types including adult weekly, fortnightly and monthly passes have already ceased – we face the prospect of stations that do not sell tickets, at all. I'm still having trouble with this. Train stations without tickets? Is this some kind of joke? My closest Opal outlet turns out to be the local Woolies. And yes they do sell Opal cards, adult and child. But no, they don't know what defines "child". (This matters because it caps your weekly spend at $30, instead of $60.) The Woolies man doesn't know how to find out, or on which services your Opal can be used. He proffers a sad-looking brochure but, on these core questions, it is silent. I head to Central, which surely must be the core repository of both cards and wisdom. But no. You can't buy an Opal from the ticket machine at Central. The man in the booth doesn't sell them either, although he helpfully defines "child" as "under 16." For the card itself he points me to the concourse newsagent. The newsagent tells me the child cut-off is 15. When I re-ask her again she re- answers with exaggerated precision, as though I'm either deaf or slow. But as to where I can actually use my Opal – which modes, which routes – she has no idea. For her, though, she assures me, on her bus route, the Opal saves money.

Until now I'd assumed it was money-saving. Indeed, as the inconvenience loomed larger I'd begun to assume it must save rather a lot. Why else would you have one? But the woman's blanket assurance made me suspicious. And the truth is no, Opal doesn't save money. Not for me. Indeed for my normal two-zone fare, it represents a 19 per cent increase over a Travel Ten. (It's a 4 per cent decrease on the current adult My Bus single fare – but does anyone even buy them, any more? It's not as if you can just hop on a bus and pay the driver, these days. Forethought is compulsory.) So it's expensive, hard to find and, when you do, of doubtful utility. I wanted a monthly pass, like my old Oyster. Pay your 30 quid and for a month go anywhere, any time, any mode. Change your mind, as much as your bus, without worrying. It makes city travel fun. But again, no. Opal makes you pay per ride. There's no option to buy bulk rides, and no weekly or monthly pass. So if you have to change or switch to get there faster, you pay again. This is ideological. Minister Berejiklian says, "We believe that customers should pay for the mode they are using."

Opal's only concession, besides age, is a weekly eight-trip cap, after which it's free. This perpetuates the principle, pioneered by the prepaid buses, of discouraging casual users and pandering to the tyranny of the majority. It also means employers should brace for epidemic Monday morning lateism, as commuters devote their first weekly trip to zig-zagging between modes and trains in order to render the rest of the week free. So we witness the bizarre phenomenon of a massive public transport initiative, decades in the planning, that makes everything harder, less fun and more expensive. It's not rocket science. The Oyster was there for the copying. Yet if you wanted to devise a way of seeming to support public transport while actually proving it could never work, this would be it. The only plausible explanation is that Opal is actually funded by the roads lobby, intent on disguising the fact that, on Westconnex costings, that $80billion tax-hole wouldn't even get us to Bathurst. Either way I'm with Alice. Opal's a joke. Twitter: @emfarrelly