The most common flaw in placement-testing is a seed network inside warmup pools. The seeds have been trained by pool interactions to accept pool mail; the resulting “placement” number is circular.
Our three commitments
- No seed mailbox registers in any public warmup pool.
- No seed mailbox auto-replies, marks-as-important, or adds-to-contacts for test mail.
- No pool operator is granted preferential treatment by our seeds.
Why this matters
- Providers distinguish between pool-originated signals and real engagement. Pool-resident seeds will accept pool mail to Inbox that a real mailbox classifies as Spam.
- Anti-spam filters weight the graph of who-mails-whom. Pool-resident seeds mail each other extensively; this is what the filter de-weights.
- A seed that participates in a pool has “seen this sender before” for any domain the pool has warmed up — even if your real prospects haven't.
How to verify we're telling the truth
- Run your draft through a warmup tool's own placement test, then through ours. The delta is the pool effect.
- Ask any warmup vendor whether their seeds are in their own pool. Compare the answer to ours (ours is “no”).
- Run the 48-hour kill test — pause warmup, measure placement on us. Stable = our number is real; collapse = you were relying on pool membership.
Hygiene practices
- Regular rotation of seed mailboxes to prevent filter over-training.
- Light, occasional organic engagement on each mailbox (inbound from real services, outbound to real recipients) so mailboxes look like real users.
- Per-seed 24h rolling cap on test inbound.
- Detection of pool-originated mail in seed inboxes with automatic flagging.
Measure outside the pool
Run a test. Seeds outside every pool, no signup, no coordination effect.
FAQ
What if a warmup vendor adds their pool to target our seeds anyway?
They'd have to successfully register in our seed network — which we don't open to automated registration. If they somehow tried, we'd detect the coordination pattern and remove the offending senders from placement reporting.
Are your Gmail seeds real Gmail accounts?
Yes. Real Google accounts with real history. Simulated endpoints don't work — Gmail's filters recognise them.
What about MS tenants?
Real M365 tenants. Real Outlook.com/Hotmail/Live consumer mailboxes. We rotate and maintain them.
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