P&G without neutral (I called it Pulse & DFCO) was worse than steady driving in my 2008 VW, and logically it would be worse in any car.
i'm still learning my civic(had it only a few months), but i'll have to disagree here. i've tried both cruise control and P&G w/ DFCO, and at high speeds the latter yields a few more MPGs...scan gauge and fill ups both confirm.
For open freeway driving, cruising at 60 is decent. Gains could be found using DWL, pulse & glide (neutral), pulse & EOC (given rolling hills), or drafting.
That said, on the freeway P&G or P&EOC is too much work for too little gain unless your car is dense and very aerodynamic. I EOC down one freeway hill on my commute but otherwise I do something similar to DWL (DWL doesn't apply on my carbureted car but I keep a target vacuum level in mind).
Cruising at the slowest speed you can gets you the best no-effort fe. 55 mph beats 60 mph, 50 mph beats 55, and 45 mph beats 50. So pick the road with the lowest posted speed limit, and drive at that speed, or 5-10 mph below the PSL, if there's no other traffic to impede. On cruise control, I get 50-55 mpg at 30-35 mph, 40 mpg @ 55 mph, and 32 mpg @ 70 mph.
P&G beats steady speed cruising. It adds ~5 mpg on highway trips, and 10-15 mpg under city/country road conditions. I get 45-52 mpg P&G between 50-60 mph, 55-65 mpg between 25-40 mph, and 60-72 mpg between 20-30 mph.