Here goes my 101 explanation 
If you’ve ever ridden a bicycle with gears then you understand how cars and bikes work. On a bicycle you have the option to stop peddling while the chain jumps sprockets (otherwise bad things might happen), on a car/bike this is what the clutch does. It disconnects the power of the engine from the wheels while it changes gear. Trials is right in that it can be a hard skill to learn but it soon becomes 2nd nature and makes the driving/riding much more involved and therefore satisfying.
I think his bias is showing though when saying standard is always better. If you think about it, the fact you have 5 or 6 gears means you are almost always in a sub-optimal gear. If you accelerate from 0-60 working through the gears, for each one there is only an instant where it is the perfect gearing ratio. A Continuously Variable Transmission (CVT, or the rubber band Trials mentions) is allegedly always in the perfect gearing ratio. This rubber band sits on a cone and it alters the ratio by moving up and down the cone (the continuously variable part). There are other inefficiencies however that hamper the design. But consider this, in the early 90’s the top team in Formula 1 at the time experimented with a CVT design. Allegedly their number 2 driver was able to knock several seconds off his lap time. Since this wasn’t a Ferrari, the FIA banned it!
Automatic transmissions are making a revival again, even on bikes. Honda seems to be developing at least 3 different types of auto transmissions (not all are CVT) and these bikes are hitting the showrooms today. Time will tell if they take off but I’ve read at least one moto hack ask what’s so great about having to shift.
