Unfortunately this relies on PMTU discovery working, which is frequently broken by misconfigured firewalls by eg blocking all ICMP traffic. Now that GCE has a m

Unfortunately this relies on PMTU discovery working, which is frequently broken by misconfigured firewalls by eg blocking all ICMP traffic. Now that GCE has a more exotic broken firewall that also breaks traffic with PMTU disabled, you have a lose-lose situation.