Based on the financial data provided for ERG S.p.A. for the fiscal year 2022, the recommendation is to target a 0% threshold for hybrid bonds as a proportion of total adjusted capital. 

Here is the reasoning behind this assessment:

1. **Low Refinancing and Funding Needs**: ERG experienced a massive influx of cash in 2022 from the sale of subsidiaries/discontinued operations (generating €1.26 billion in cash flows from losing control of subsidiaries). The company used these proceeds to drastically reduce its debt load, reflecting €1 billion in cash outflows to pay down short-term borrowings and €350 million to repay non-current borrowings. Consequently, their near-term refinancing needs are virtually non-existent.

2. **Improvement in Credit Metrics**: The company exhibits an extremely robust leverage profile. Operating cash flows generated from continuing operations reached an impressive €502 million. Meanwhile, EBITDA (Profit from operating activities before D&A) increased materially from €396.6 million in 2021 to €499.4 million in 2022. This organic earnings growth combined with significant absolute debt reduction structurally improved leverage and rating metrics on its own. 

3. **Cost of Debt vs. Cost of Hybrids**: ERG’s interest paid in 2022 was just €29.1 million against a substantially larger debt base, implying a very low prevailing cost of debt. In contrast, evaluating the 2022 swap curve and the sub-senior delta for EUR non-financial corporate IG issuers, the cost of issuing hybrid bonds surged during the year (with typical sub-senior deltas at ~2.3% and swaps nearing 2%). Therefore, injecting hybrid capital would materially and unnecessarily increase the company's weighted average cost of capital.

4. **No Transformational Capex Pressure**: While the company continues to invest in property, plant, and equipment (€307 million), its robust operating cash flow comprehensively covers its capital expenditures, translating into healthy free cash flow without the need for hybrid equity credit. 

5. **Capital Structure**: There is no existing record of hybrid capital in ERG’s current capital structure, and maintaining a straightforward senior debt structure continues to be the most optimal and cost-efficient path to support its investment-grade rating profile.

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