How would providing a "really, really old pay stub" showing "much lower pay" provide a) proof of CURRENT employment and b) help with negotiating a salary higher than your current salary? The advice he gave was nonsense.
Repeat after me: it is none -- NONE -- of their business what you currently make. When a company asks for salary history, they're trying to filter you out and you never give it to them. Instead, ask them the salary range for the position. If they won't give that to you and still ask for your salary, just tell them the range of pay you're looking to make in the new position. If they still insist, tell them to get bent.
OP, just give a paystub and black out the numbers.
If I'm hiring a sales director who claims he hit 150% target and was paid $300k in commissions, you bet it's my business what they really made.
