Adding Single Pass Rendering to a modified Standard Shader

I've modified the most basic Unity Standard Shader to add Tesselation and it's working great except in VR (when using single pass rendering).
I'm trying to find a good example to add Single Pass Rendering but all the examples are for vertex/fragment shaders , nothing for Unity Standard shaders.
Does anyone has a link I can follow to a working sample?
Here's my current shader:
Thank you.

Shader "Custom/StandardTesselation"
{
Properties{
_MainTex("Base (RGB)", 2D) = "white" {}
_Color("Color", color) = (1,1,1,0)
_SpecularColor("Specular Color", color) = (0.5, 0.5, 0.5, 1)
_Smoothness("Smoothness", Range(0.0, 1.0)) = 0.5
_GlossMap("Gloss Map", 2D) = "gloss" {}
_BumpMap("Bumpmap", 2D) = "bump" {}
_BumpMapDetailScale("BumpmapDetailScale", Range(0.0, 1.0)) = 1
_BumpMapDetail("BumpmapDetail", 2D) = "bump" {}
_EdgeLength("Edge length", Range(2,50)) = 5
_Phong("Phong Strengh", Range(0,1)) = 0.5
}
CGINCLUDE
#define _GLOSSYENV 1
#define UNITY_SETUP_BRDF_INPUT MetallicSetup
ENDCG

SubShader{
Tags { "RenderType" = "Opaque" }
LOD 300

CGPROGRAM
#pragma surface surf StandardSpecular vertex:dispNone tessellate:tessEdge tessphong:_Phong nolightmap
#include "Tessellation.cginc"
#include "UnityPBSLighting.cginc"

struct appdata {
float4 vertex : POSITION;
float4 tangent : TANGENT;
float3 normal : NORMAL;
float2 texcoord : TEXCOORD0;
};

void dispNone(inout appdata v) { }

float _Phong;
float _EdgeLength;

float4 tessEdge(appdata v0, appdata v1, appdata v2)
{
return UnityEdgeLengthBasedTess(v0.vertex, v1.vertex, v2.vertex, _EdgeLength);
}

struct Input {
float2 uv_MainTex;
float2 uv_BumpMap;
float2 uv_GlossMap;
};

fixed4 _Color;
fixed4 _SpecularColor;
sampler2D _MainTex;
//half _Metallic;
half _Smoothness;
sampler2D _GlossMap;
sampler2D _BumpMap;
sampler2D _BumpMapDetail;
half _BumpMapDetailScale;

void surf(Input IN, inout SurfaceOutputStandardSpecular o) {
half4 c = tex2D(_MainTex, IN.uv_MainTex) * _Color;
o.Albedo = c.rgb;
o.Normal = UnpackNormal(tex2D(_BumpMap, IN.uv_BumpMap)) + UnpackNormal(tex2D(_BumpMapDetail, IN.uv_BumpMap)) * _BumpMapDetailScale;
o.Alpha = c.a;
o.Specular = tex2D(_GlossMap, IN.uv_GlossMap).rgb *_SpecularColor.rgb;
o.Smoothness = _Smoothness;
}

ENDCG
}
FallBack "Diffuse"
}