The claim is directly supported by The Kobeissi Letter post at https://x.com/KobeissiLetter/status/2046237703532916784, which states the +0.55-point increase and describes the metric's coverage of institutional investors. However, no authoritative primary dataset, research note, or official report confirming that figure or the 'largest weekly increase in 8 years' framing was found in this run. The fetched Bank of America page titled 'Must Read Research' does not validate the numbers. Therefore, the claim may be accurately relaying a market commentary source, but the available evidence here is not strong enough to rate it likely true with confidence.