Not really. Actually, I've never handled a 28" box lock gun, of any nationality, that I felt was barrel heavy. I have, and shoot, boxlocks with from 26" to 32" barrel lengths, and I can honestly say dynamics have little to do with barrel length. Gun designers and barrel strikers can make a 32" gun handle almost whippy, or make a 28" barreled one handle sluggishly. Each gun has to be evaluated on it's individual handling characteristics, regardless barrel length. That said, I find myself to be much more favorable of longer 30-32" barreled doubles than shorter 26-28"ones.
Trying to come up with a standard, as you're doing with 28" guns, assumes that all shooters are built the same, with the same length arms and musculature. But, we are not. Longer armed shooters have greater leverage on the gun, and a 32" barreled gun, for them, may handle the same as a 28" barreled one in the hands of a shorter armed shooter. The possible combinations of arm length, musculature and shooting style are endless. Thus, the individual preferences of shooters. Hence, what you refer to as barrel heavy may feel entirely different to me.
SRH
