However, AFM/regulatory OEI limit generally is 15 degrees due to climb degradation. Company procedures may reduce this for specific escapes generally to constrain turn radius for threading one's way around the rocky bits.
Ah so, there is a track consideration, but not regulatory in nature - more cautionary on the part of the company flight procedures group.
For OEI - until one has a goodly speed margin and terrain is no longer a concern - more than 15 degrees is, in this ops engineer's view .. a tad silly.
Agreed, Sir John.