The first thing I thought of, when watching the video of Windows 7's new multitouch interface was 'oh no, not again'.
Not because it looks like the iPhone's interface scaled up (although, with a tedious inevitability, it is), and not because the things it showed off were the sort of things you could do perfectly well with existing user interfaces.
I'm talking about gorilla arm.
Gorilla arm, for those not involved in user interface design in the 70s, is the shorthand for the discomfort experienced by people who had to use light pens on vertical monitors.
Light pens were light sensors in a pen-shaped holder, connected to the computer by a curly lead. If you held one to a screen, it would send off a signal at the moment the cathode-ray tube dot scanned past, and so it was possible to calculate exactly where on the screen the user was pointing.
Light pens had a lot of things going for them. They were simple, accurate and didn't need much software or modifications to the computer to make them work -- all important factors in the days of tiny RAM and expensive processors. Manufacturers and software designers loved them.
But there was one small snag. The human arm - remember humans? - isn't designed to be held horizontally away from the body for any length of time while making tiny, precise movements. Tasks that took any time to complete, including navigating through menus, soon resulted in aching muscles, stiffness and a swollen feeling -- gorilla arm.
Telegraph operators used to get a similar condition called glass arm from bashing badly-positioned morse keys all day, but they'd long gone by the time computers turned up so nobody remembered. Technology's like that.
However, the epic fail of light pens was so substantial that the phrase gorilla arm came to mean any form of ergonomic cock-up where real life gets in the way of designer dreams. Light pens vanished from the world, and lessons were learned.
And that was that. Until Microsoft thought the best thing to do with the iPhone interface - which lives in a small, thumb-based world in your hand where alternatives don't work - was to put it on the big screen, where none of that is true.
Yes, it might work for tablets - but who uses them? In any case, Microsoft is thinking bigger than that. It even demonstrated the thing on a vertical screen.
As with so many high-profile OS-based MS decisions, the question keeps asking itself: what problem is this trying to solve?
There is talk afoot that Apple is finding itself with increasingly substantial corporate sales, despite not having any form of corporate strategy, because people are so plain fed up with Microsoft that they're swallowing the pain of switching their enterprise IT.
It's probably far less painful than gorilla arm.