he was still testing for IE7 and had just stopped testing for IE6 a few months before... I know some sites don't even test for 9 only for 10 and 11 right now.

that's more focused no? In Enterprise you generally use just one browser no?

Last year i delivered a responsive site for a global bank, and the year before that.., a telecom company.

IE8 was the lowest target for the bank. IE6 was the lowest target for the telecom company.

The general rule of thumb, is to make the site useable, without the bells and whistles. But sometimes, you'll have to go the distance by using polyfills etc. to please the client.

Lately, I've seen a massive shift in the enterprise - to Chrome.