"I just got a pair of Sidi shoes. Before this I wore mountain bike shoes. I am finding it very difficult to get going after stopping because the bottom front of the shoes have nothing to provide traction. How can this be remedied?"
Mindi, I would appreciate a little more on the exact nature of the problem.
Supposing you are on a single bike in the normal starting position, that is, strong foot clipped in (you are using clipless pedals and/or toe clips and straps?) at about the 2:00 position on the pedal circle (a little bit after top dead center), and some part of the foot on your weak leg on the ground (just the toe is okay), and with your bottom on top of / on the point of / just in front of the saddle, pedal with the foot that is clipped in, steer (not much) under the lean toward the foot on the ground if you had to (this foot is already well on its way to its pedal by now), put your bottom back and up onto the saddle if you had to while you are obtaining the lift to do this from the first pedal stroke from the foot that was already clipped in, and you are gone, gone, gone. No dabbing with the shoe to move forward is required. Your other foot usually meets its pedal at the top of the stroke, and lines up and locks up on the way down or at the bottom.
Of course, since this is a TANDEM forum, we have to talk about how to do it on a tandem too. If you are a captain that starts with your stoker already clipped in, the above directions apply. If you are a stoker that starts already clipped in, the question does not arise, save to say that a very brief pause at the top of the first pedal stroke to let the captain get lined up will be appreciated. If you are a team that starts off two feet on the same side (one captain foot, one stoker foot), then the above directions apply, except that being more rigorous about the steps helps get it right the first time. So I say "1, 2, 3, go, half stroke and coast, line up, LOCK up, I'm in, you're in (are you in?), GO. And we just go clickety-click.....
I count down to start, which supplies a starting signal and some idea of the step rhythm, we take that HALF STROKE to the bottom of the pedal stroke for the feet that were already clipped in, LINE UP the other cleats on top of the pedals that are now easy to reach at the top of the pedal stroke, take another half stroke to the bottom for the feet that are in the process of clipping in, and on the way, or at the bottom, I will hear the cleats pop in, and I will say "I'm in, you're in," unless I didn't hear my stoker get in, in which case I will ask, "Are you in?" If neither of us is sure, we won't start pedaling, but instead wait for a cue from the other. If either of us is sure, there's no pause at the bottom of that second pedal stroke. My stoker is better than me at getting clipped in, so she usually beats me and as soon as she hears mine slam in, she knows to keep going.
The right gear to do this in is the one (there will be more than one) that supplies enough speed so that you can coast for a few seconds after the first half-stroke while you are fooling around with getting your cleats in the pedals. Doesn't matter going downhill, of course. Going uphill, if you are too low, you won't have enough speed to maintain balance for long enough to finish the job, Too high, and you won't have enough power to get up enough speed to do the job either. If you are too high, usually what happens is that you make it to the bottom of the first pedal stroke, but without both feet in that's as far as you have the strength to go, and you end up dabbing before you get the other feet in.
Most of us are careful not to scrape our sole-less racing shoes on the ground. They will last practically forever (five to seven years with ski-buckle latch, perhaps more) if they don't scrape on the ground, but if you think you have to scrape yours on the ground, I'm not going to say you can't, and I will even say you could glue some inner tube rubbber to the bottom where you need it.
If we didn't answer the question you thought you asked, ask again.
Jury duty tomorrow. If they bounce me early for insisting on material evidence where it can be reasonably be expected (hey we're talking about proof beyond a REASONABLE doubt, right?), then maybe I can get a single bike ride tomorrow.