Thanks for your responses.

The reason this issue came up is because some SIDS have rather demanding climb gradients. Should one lose an engine, these gradients are often impossible. I understand that engine failure and TERPS are independent. TERPS is for all engines operating. With an engine failure, responsibility lies with the operator.

With charter operators and perhaps with fractional operators, airport analysis (AC 120-91) is cost prohibitive. So I was wondering, as long as I can achieve 3.3% could I still fly the SID and remain clear of obstacles, even if the SID required a steeper climb gradient, presumably for ATC reasons.