Second, even if it was well done, it may have spread much less widely than people suppose.

【翻译】其次，即便此事能成，效果也远远不像人们所认为的那样得到了广泛推广。

 【分析】为了理解，作个对比：

1. more widely than：比.....广泛

2. much more widely than：比.....广泛得多

3. less widely than：比.....不广泛

4. much less widely than：远不如.....广泛