This is an a priori defence of the Potion of Giant-Strength in Stormslayer.
1 “Your skill score may change occasionally during the course of the adventure, but it may not exceed its Initial value unless you are specifically instructed to the contrary”.
1a You are told your skill score may change occasionally.
1b You are told you cannot increase your Initial skill without specific instructions.
1c You are told if you are given instructions to the contrary you are to obey those instructions.
2 “It will raise your skill score by 2 for that one battle and the damage you cause by 1 point”.
2a This is the occasional change.
2b This is not an increase to Initial skill but an increase for one battle only so it would be irrational to say it is an increase that requires the words Initial Skill as that would imply a permanent increase as in Howl of the Werewolf or a permanent increase due to using an item of equipment as in Night of the Necromancer.
2c This is the instance where you are being specifically instructed to the contrary.
3 There is one instance where you are instructed to restore your skill to its initial value and this is entirely in keeping with the above.
4 Why does this rule not follow the logical form of Wyrmbiter where it is an addition of 2 to attack strength and 1 to damage? The reason is the Potion is an instance where your attributes are being temporarily improved whereas Wyrmbiter is an item of equipment that enhances your attributes. Stormslayer obeys logical form impeccably and if the care and attention lavished here were absent we could not take advantage of the most powerful Potion we are offered for free. Also if you play by the rules, using my parsimonious system as a yardstick, you have the chance to buy another Potion as it is so powerful.
5 If we turn our backs on this we are destructuring Stormslayer unnecessarily.