Hi, i was having a discussion and, i believe it was asserted that gallic, and other celtic iron age long swords were very blade heavy and suited most to large over the shoulder chopping strikes

i'm thinking primarily around the time of the roman era for the most part

those who have made exacting replicas etc, what are peoples impressions?

There are some very big late La Tene swords with round points for which such a statement might be true, but since the first contacts between Rome and Celts to the conquest of Gaul, even in just the last years of this period, the varieties in the celtic swords are huge. Long, parallel sided cutting swords, shorter cut and thrust ones, rapier like ones, various cross sections, diamond, lenticular, hollow ground, various sizes, from the size of a typical gladius to the size of medieval longsword... There is no rule...

"Blade heavy" is fair, but that's usually matched with a fairly light overall weight. The blades are typical enough sword blades, and the hilts are usually light. So the point of balance is fairly far out along the blade (8" would not be unusual) - this is what people will generally call "blade heavy".

People who haven't learned how to use swords might feel that "large over the shoulder chopping strikes" are natural with it, but I think they'd say the same of many different swords, of varying weights and balances. Looking at some common pommels, I think that the Celtic long cutting swords are best suited to slicing draw cuts, and with their light weight, from whatever angle you want.

(I'd say the same thing about using Viking swords, too. Slicers, not choppers. Viking hilts are very draw-cut friendly, like a European version of a tulwar hilt.)