You've got it wrong, Mike.
The rules were indeed changed because the original statutory holiday entitlement (for those who work 5 days per week) was 20 days per year. The Government had wanted that to be in addition to public holidays but many employers chose to include public holidays within those 20 days.
So (as your post suggests) the rules were changed to give back the 8 days of public holidays to such employees. However all that happened was that the minimum entitlement was extended to 28 days. As long as employees receive that entitlement (which could be on days entirely of the employer's choosing), the employer has discharged their statutory duty.
Quote 1:
"You don't have an automatic right to paid leave on bank and public holidays"
Source:
http://www.direct.gov...vingintheUK/DG_073741
Quote 2:
"Bank and public holidays can be included in your minimum entitlement"
Source:
http://www.direct.gov...dholidays/DG_10029788
Chris