You say that like there's a difference.

There is.

Crack is cheaper.

You got some interesting replies. It is good to maintain your own sense of perspective, something which varies with the person giving advice!

Pretty neat, huh? It does suggest that your mtb wasn't doing it for you, since you never rode it.

Depends on how fit you are, how you feel, how hard and long you ride, etc. Your body will tell you when you've overdone it. You are a youngster. Enjoy it.

Be suspicious of any figure like 40%! Here is where perspective comes in. I've been told that it is "the most significant improvement" in years. But I've ridden with clips and straps for decades and rarely felt any limitation. (Of course, I wouldn't know, would I?) I don't have a problem picking them up and with the right shoes (a choice of running or cross-training shoes) never have a problem getting my feet out in a hurry. However you can read stories here in BF of experienced rider falling over because their pedals wouldn't release.

Finally, consider the possibility of wanting to bike but either your specialized shoes aren't available or they aren't appropriate for when you get to where you are going. In the old days you could see penguins hobbling around wearing bright colored bike suits and shoes totally inapropriate for walking even 10ft. If you bike 16 miles (I think you wrote) to class, do you want to wear those bike shoes all day or pack other all-day shoes with you? If you go to clipless pedals, will you have any other choice? If you aren't racing and you aren't running out of energy on your typical fun rides, is this still a price you are willing to pay? I suspect your typical BF reader will say yes. (But then, many of us still ride old steel bikes and still enjoy it.) So the answers you get to this question are probably skewed. When you have developed a sense of what is important to you you will be able to make this decision.

Your cadence will rise as you gain time on the bike. Curious choice of words, though. "Push harder" could mean push the pedals harder to go faster, or it could mean work toward a higher cadence which means getting comfortable using a lower gear.

Events to enter? You want to race now? Get some time on the bike first. You want to ride with cycling groups? Be able to keep up with them! You want to ride a century? Be able to ride that far, starting small and increasing your distance.

Finally, other things to work on? Just being comfortable under different situations. Going uphill. Pacing yourself. Learning to read road conditions, wind conditions, traffic patterns, other riders' habits, etc. Bike maintanence, fixing tires on the road.

Have fun. Welcome to the club!

I'm not embarrassed (well not that much) when my car breaks down and I must pull over. Niether should I be embarrassed when a small error momentarily slows the traffic behind me. I do feel that way to be sure if my chain skips a gear on one of my old worn out bikes, but it's not going to keep me off the road!

I dunno about that-- even an expensive bike can work out to be a bout $5 per "hit."

And the high can last just about as long as you want!

I think you are exaggerating these problems. One can use MTB "SPD" shoes that are OK to walk around with. It's often not a big deal carrying an extra pair of shoes (if you are carrying other stuff). You can even get pedals that are platforms and clipless (you'd have to forgo clips and straps). But, if people don't want to use clipless pedals, there's no problem with that.