There a point where frequency simply becomes overkill and clogs up the airspace and runways, especially in the Northeast Corridor (cough PHL cough). Especially when the RJs use the same amount of airspace and runway space that a 737 or A319/320 takes up.

Some examples:

MDT-PHL 9 daily Dash 8s
PWM/DTW-PHL 6 daily CRJs plus 1 E170
GSP/AVL-CLT 8 daily CRJ/ERJ/DH3 round trips
TYS-CLT 7 daily Express round trips

I'm mildly shocked at ATL-CLT: 8 daily CR9/CR7/CRJ round-trips-all Express, its not exactly a small city pair-and with the advent of US West's multiple flights to LAS/PHL, its going to be a mainline station anyways. Same with DTW and CLE (not mentioned but it has 6x daily to PHL).

Looking at some of these frequencies, its not that surprising why you're in the world's longest conga line for take off at PHL. I'm not saying that Express doesn't have a place in the system, but 8-9x daily with what are for ATC purposes mainline jets is ridiculous. Now, personally I'd prefer something in the middle, like 3 daily A319s/733s and 2 50 seat Express planes. Any more than about 5x daily to most of these cities is overkill and would go a long way towards improving "dysfunctionPHL".

BTW, the CR9 is the spawn of Satan. Can't we in the East get anything good from US West instead of just their reject Express aircraft?