Porters' 5 forces

I was giving a seminar, a few years back, about new market entry, to a group of young marketing executives. When the subject came to the well known Porters’ 5 forces I asked of how every one was interpreting this theory in real life business competition. The answers I got back were confusing, to say the least.
Setting things straight:

Barriers to Entry. Force applies with:
Economies of scale
Proprietary product differences
Brand recognition
High switching costs for the customer
Capital requirements
Difficulty to access distribution channels
Absolute cost advantage of incumbents (Learning curve advantages, Access to necessary inputs, Proprietary low-cost product design)
Government regulation, restrictions on entry
Expected retalitation

Buyer Power Force applies with:
Bargaining leverage
Buyer concentration, Small number of buyers
Low buyer switiching costs
Buyer information
Byuer ability to integrate backwards
Availability of substitute products
High price elasticity
Low product differentiation
High brand recognition
Low impact on buyer‘s product quality
Decision maker‘s incentives

Rivalry Force applies with:
Industry growth
High fixed costs + low variable costs
High value added
Intermittent overcapacity
Low product differentiation
Low brand recognition
Low switching costs
Number of competitors
Corporate stakes
High fixed costs or high specialized assets
High barriers to exit

Supplier power Force applies with:
Differentiation of inputs
Importance of supplier‘s product/services in cost
Structure of industry
Lower switching costs of suppliers
Higher impact of inputs on cost or differentiation
Lower number of substitute inputs
Higher threat of forward integration
Lower importance of volume to suppliers
Lower Supplier concentration

We do not neglect to consider X factor which could be from government impact (a feed in tariff or a hostile policy) to a brand name that sounds funny in local language (try slogan-ing a German cleaning service in German language “cleaning around for you” in Greece and you’ll get a sexual services slogan.