Here is what I'm trying to do, but with not quite complete success:

1) set a micro break for every 10 minutes that lasts 15 seconds.
2) set a normal break every 24 minutes that lasts 6 minutes.

A typical hour would look like this:

10 - micro break
20 - micro break
24 - normal break
40 - micro break
50 - micro break
54 - macro break

What is happening is a get 1 micro break for every normal break, rather than 2 micro breaks. The first one comes at 10 minutes, but the micro break at 20 minutes doesn't seem to get triggered. In other words I get:

10 - micro break
24 - normal break
40 - micro break
54 - normal break

I'm wondering if I'm missing something simple?