The relevant section from the "old vs new comparison" PDF:-

Old
"Two in a bar" rule means that where
more than two artists perform a public
entertainment licence is required, often
at considerable cost, even though one
performer with an amplifier can make
more noise than three or more.

New
All public entertainment will require a
licence but it will cost nothing to add
this to the list of activities undertaken eg
where a licence for sale of alcohol is
being obtained – resulting in a big
increase in opportunities for musicians to
perform and a corresponding increase in
choice and variety for the consumer.

As long as your publican has enough brains to fill out a form to add live music to his license (which won't cost him anything except the time to fill out the form), I don't see there's a problem. If he doesn't, there's really no-one except himself to blame.

Grab.