Why are graphite shafted irons 1/2" longer than Steel Shafted?
Convenience for mass manufacturers of clubs is the main reason for the different club length.
If you put a much lighter shaft into a clubhead, its swingweight drops like a rock; a swingweight that is too low makes a bad club for most golfers.
To resolve this issue, there are three choices:
• To manufacture and stock up iron heads in two different weight versions. This is inconvenience or expensive.
• Design iron heads with weight ports so that weight can be added to the head for assembly with graphite shafts. Iron heads with a weight port don’t look nice and are also more expensive.
• Increased length of a shaft, let the head feel ‘heavier’ = higher swingweight. A longer graphite shaft allows the club companies to use the same heads on both steel and graphite shafts.
If club companies cut the graphite shafts a bit longer, the swingweight will come out the same.
The question is: do you want your iron clubs to be longer?
If your wrist-to-floor measurement plus a swing analysis says that your #5-iron length should be 38 inches, then it should be indeed 38 inches regardless what shaft goes into that 5-iron.