The events at NHMS are similar in my mind to the events at Summit. Each has enough of a constituency to run events with just there regulars so there is no reason to drop events there. We do a lot of data analysis on entries. Last year when the gas price spiked at $4 per gallon we ran a very good event (170 cars I think) and going over the entry list found only three drivers not from New England. 5 regional weekends is not too much at NHMS.
Now the National we only do as a perceived obligation to our regions national drivers.