Walkable urban environments are good. One characteristic that makes an area walkable is the provision of means to walk from one location to another in a fairly direct manner. Having a highly connected street network is advocated as a means to accomplish this. And it does.
What the advocates of connected streets fail to see, however, is that having a connected street network is not necessarily the only way to ahieve the desired objective. Connected streets are required only to the extent that the only paths for walking are sidewalks at the sides of the streets.
Paths can be provided for walking that are separate from the street network. Such paths have advantages and disadvantages compared with sidewalks along the streets. But they definitely represent an alternative to connected streets for providing more direct ways of walking from one place to another.
Radburn, New Jersey, was designed with a system of pedestrian paths that were grade-separated from major roads. Greenbelt, Maryland, the depression-era planned community, likewise included such paths. Moving forward several decades, the planned communities of Columbia, Maryland, and Reston, Virginia, included extensive systems of walking paths separate from the street system.
When I first moved to Irvine, California, in 1974, I lived in an apartment adjacent to one end of University Park, one of the early single-family residential developments in that planned city. At the other end was a small shopping center with a modest supermarket and a few other establishments. University Park had an extensive system of interior walking paths. I would frequently use those paths to walk to the market, as I found it more pleasant than walking along the streets.
Walking along separated paths or along a street each have advantages and disadvantages, depending on the situation. The separated path, especially if nicely landscaped, can be pleasant and tranquil. On the other hand, it may not have much activity. Some streetscapes can be more interesting to walk along, while others bordering a major road without other interesting activity can be far less pleasant.
One more thing. It can be easy to turn cul de sacs, the bane of the connected street advocates, into walkable settings. This is especially easy if the cul de sac is extended close to an adjacent street with no house built at the end of the cul de sac. Simply put in a short path from the end of the cul de sac to the adjacent street. This alternative is fairly common in my neighborhood in Upland, California, which is east of Los Angeles. Here is the satellite view from Google Maps showing the path (obscured at several points by trees) from the end of the cul de sac to the sidewalk along Mountain Avenue (that sidewalk is also obscured by the continuous line of trees along Mountain Avenue):
And here is a ground view of the path from the end of the cul de sac looking west towards Mountain Avenue: