What is the ROI on employee suggestion systems?

Bring up the phrase "suggestion system" and most managers bristle at this taboo discussion. Here is a great example of why we should engage in kaizen teian everyday - example provided by Anshu Jalora on the LinkedIn network:

Around early 90s, a leading toothpaste manufacturer in India was faced with the challenge of increasing its sales. The sophisticated approaches developed by the marketing and sales personnel, who had big degrees from top business institutes (Harvard, Stanford, IIMs, etc.) were having little effect. VP-marketing wanted an innovative approach, and opened the floor to all employees of the company to give suggestions. They received a very interesting suggestion from a junior shop supervisor. His suggestion was to increase the diameter of the opening of the toothpaste tube by 25%. If this is done, then for the Same length of toothpaste squeezed out, the volume will be 56% more. More consumption, more sales. His suggestion was accepted, and the company noticed an increase of 20% in year over year sales. Simple enough!