Hi

I'm tidying up my site and had a few questions ref: use of headings.

1. My previous SEO company use to reduce the font size for headings, this seems a bit black hat to me ? Is this okay? For example heading text as font 6 and paragraph text as font 12.

2. If my key search term is 'driving lessons in London' and my second key search term is 'Driving Schools London', Is it better to have my H1 as: Driving Lessons London & H2 as: Driving Schools London

OR

H1: Quality Driving Lessons in London by driveJohnson's

H2: How our driving school in London can help you:

In my opinion the 2nd one reads better and i notice other companies doing it the second way, the first way i mentioned seems a bit old school and doesn't read well ?

3. Is it worth using H3 & H4 ? Can you use H2 more than once ?

4. Lastly could i have two key search terms within one heading, as long as the paragraph underneath is about the heading. For example:

H1: Our driving school in London offers cheap driving lessons

The two keywords search phrases here for me would be driving schools London and driving lessons london.

If someone could get back to me, i would be very grateful.