A goal of a fitting would be to compare the DCI's to the new models. If the feel, forgiveness and distance don't exceed the DCI's as value to you, you can keep the DCI's. The DCI's were great in their time but over just the last 5 years, the technology of clubs is remarkably better. Paying someone to re-shaft the irons is halfway to a new set, without the newest tech.

If you decide to keep the DCI's, then time to get the clubs back to spec for loft and lie.

No.

Your 981s are pretty old, I would suggest you get fit for a new set of irons. Once you hit some of the new models you will be convinced that it's time to change. Going through a fitting will also identify which head/shaft combo is best for your swing. Use the FITTING menu option at the top of the page to find a fitter near you. Typically fitters will waive the cost of the fitting if you purchase through them. If you're not in a big hurry to get new irons, then you can wait until the spring/summer and see if there are any Titleist Thursday events near you. These event are free and you can book at 35 - 45 minute fitting session. Titleist Thursdays will also be located under the FITTING option.