So if 'flex' means 'bend under sideways loads' then a high tension spoke will flex less than a low tension spoke, and a thick spoke will flex less than a thin spoke of equal initial tension.
If initial tension is increased, spoke thickness becomes relatively less important.
If we're talking of flex as being 'bend under sideways loads', then the higher the tension would equal less flex.
NO!
If we're talking of flex as being 'bend under sideways loads', then the higher the tension would equal less flex.