Eagle question, pads different size top/bottom

Hello folks

Why are the pads different sizes in Eagle when I show/hide the top and bottom layers? I wasn't under the impression that the settings in DRC effect individual layers. If I have neither top nor bottom shown or top shown they are the larger pads. If I have only the bottom layer shown they are the smaller pads. This doesn't seem to make sense as surely if anything you'd want larger pads on the bottom as this is the main solder side?

The pic is top and bottom of (roughly) the same area

The "restring" DRC parameter has different settings for top and bottom layer...

Oh yeah, d'oh! That sounds highly probable. I'll check when I'm back at my desktop.

I made a big discovery last night which effectively amounted to a stop-the-autorouter-making-dumb-choices button. The "routing grid" setting. Put it at 5 mil and OMG! the autorouter isn't as stupid as I thought! It's slower mind you but hey ho.

Thanks
Jim