I think you'll find that if you referred to the regulation as a whole, then it makes a lot more sense. What you've quoted is only
one of
four sub-paragraphs from the AIP relating to IFR altimeter serviceability.
From the AIP, it basically says;
1. If your altimeter reads within +-60 ft of aerodrome elevation, then you're good to go.
2. If it reads
between 60 ft and 75 ft, then you can fly to another point to get it checked (or serviced).
3. If it reads
more than +-75, then it's unserviceable and you need to fix it before you can depart and operate under IFR. (ie, you can't fly to a another point to check it; you need to fix it at your current aerodrome.)
4. After flying to the second point (with an error of not more than +-75ft), you find that the altimeter still does not read within 60 ft, then it's US and you need to fix it.
Well, that's the gist of it. Here's the relevant section of the AIP. Read it as a whole and it makes more sense.
ENR 1.7 ALTIMETER SETTING PROCEDURES
1. PRE-FLIGHT ALTIMETER CHECK
1.2 IFR Altimeters
1.2.1 With an accurate QNH set, the altimeter(s) should read the nominated elevation to within 60FT. If an altimeter has an error in excess of ± 75FT, the altimeter must be considered unserviceable.
1.2.2 When two altimeters are required for the category of operation, one of the altimeters must read the nominated elevation to within 60FT. When the remaining altimeter has an error between 60FT and 75FT, flight under the IFR to the first point of landing, where the accuracy of the altimeter can be re-checked, is approved. In the event that the altimeter shows an error in excess of 60FT on the second check, the altimeter must be considered unserviceable for flight under the IFR.
1.2.3 An aircraft fitted with two altimeters but requiring only one for the category of operation may continue to operate under the IFR provided one altimeter reads the nominated elevation to within 60FT. Should the remaining altimeter have an error in excess of 75FT that altimeter must be placarded unserviceable and the maintenance release appropriately endorsed.
1.2.4 When an aircraft is fitted with only one altimeter and that altimeter has an error between 60FT and 75FT, flight under the IFR to the first point of landing, where the accuracy of the altimeter can be re-checked, is approved. In the event that the altimeter shows an error in excess of 60FT on the second check the altimeter is to be considered unserviceable for flight under the IFR.