Phil,
If a fellow comes in with a broken rod and wants to go fishing and not spend more than $20 to go fishing, the only option is to repair the rod. I assure you, that if a person wants a rod repaired for $20, he could likely care less as to the weight of the rod.
One can do a very nice repair with little change in the flex arc of the rod using the right materials and typically spend no more than 30 minutes for the job, except for the drying time of the thread wrap at the ends of the repair.

I will say that I have repaired many many rods and have never had a repaired rod break at the original break or within several inches of the break. I have had repaired rods break because they were caught in a door again and smashed, but the original break repair did not fail.

Simply put, some folks are really not very careful about how they threat their rods.

I remember I had a friend come in with a broken rod and he said that there were three folks in the boat and on one afternoon fishing trip is some rough weather, every person ended up with a broken rod. One had an engine cowl fall on a rod, during a mid lake engine fix. One rod broke because someone sat on it where it had been laid down to help with the engine repair and another rod broke because it had been laid down on the floor on the front step to the front deck and someone stepped on the rod.

A bad afternoon for fishing rods, but as I said; there are some folks who simply aren't aware of where rods are in the boat.

I try to make a point when fishing in my boat, that a fishing rod is either in a fishing person's hands, or in a rod holder. Not leaning on a seat or the side of the boat and not laying on the floor. Really helps to minimize rod damage accidents.

Be safe

Diameter to stiffness is at play here. You can put a larger diameter glass sleeve over a smaller diameter carbon blank and not change the stiffness (precisely why you would always use a glass sleeve when repairing carbon/graphite rods). If you used a carbon over-sleeve, the stiffness would naturally increase due to the greater diameter of the sleeve. So when using an over-sleeve, you use a lower modulus material.

Obviously weight has to increase, but weight does not greatly affect action nor power. What it does affect is "speed," - the rate at which the rod reacts and recovers. Another reason not to employ both an inner splint and an oversleeve. Keep the additional weight to a minimum.

A repair made in or nearer the butt section, where greater strength is needed, can sometimes get away with both an oversleeve and inner splint. Weight also increases in that instance, but due to it being lower in the rod and further from the tip, any change in speed is largely unnoticed.

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