Noob, it’s a conversion, as follows: Buy land and immediately freak out -> buy stock in INTC -> short the 40 synthetic out to Jan25 and laugh all the way to the bank.
The 3.5% p.a. on average (even up to 5.0% p.a. with some stocks) is true arbitrage, is real and repeatable, not just "possible". I don't know whether it's maybe b/c of implied dividends or so, or maybe some steady historic company earnings or so. I haven't analyzed such fundamental factors, just the current market prices.
You haven't done it, so again it is all theoretical. Nothing wrong with being theoretical about something unless you make assumptions claiming it as fact.