Often times when you start the run your legs feel very heavy and it is hard to find a good smooth stride. In addition, I hear about folks whose calves and quads are very tight at the start of the run. One of the things you can do to help is to do what you mentioned.  I like to shift to an easy gear and spin fast for about 1/4 of a mile right before I get off the bike. I also stretch my calves out while I am on the bike to aviod tight calves on the run. This can be done very easily, at the bottom of your pedal stroke simply lower your heel down below the horizontal plane of the pedal. Dont do this stretch while you are pedaling... do it while you are coasting.

Some will argue that spinning and stretching on the bike is a waste of time because... you do go slower. But you usually make up for it on the run as you are able to get into your natural stride  a lot faster. 

Spinning with a high cadence like that and stretching my calves helps me avoid that "wobblie" feeling and allows me to "get my legs back" a lot quicker than not doing so. So to answer your question, I would say yes, that is correct.

Hope that helps. Best of luck.