Should users flag "subtle" spam as spam

Question

When reviewing Low Quality Posts today, I came across this answer (SO 10K only):

The bitly link goes to https://www.youtube.com/watch?v=X95lZNPAFI0.

On its own, the answer is complete crap (nothing more than a link to a tool, claiming it would solve the OP's problem), but hardly anyone selling Gucci Bags.

But a few reviews later, I came across virtually the same answer and saw it was from the same user. Further investigation showed the user posted at least 4 answers with similar content all within that hour. So taking the other posts into account, the users recent answers start to feel very spamish.

Since the spam was not obvious, I flagged as "Other" and explain the situation as we've been told to do in cases of less than obvious spam.

The question is should we be flagging these posts as spam in addition to using the "Other" flag? Would doing so help improve the spam filter, or is it better to just skip the spam flag all together except in cases of obvious spam.¹. Does the answer to this depend on the user's other posts? Would the correct course of action depend on the user's other content (i.e. limited history of non-spam posts vs 100% spam)?

^{1 - I do realize the less obvious spam is more likely to get declined by a moderator but I don't really care about a few extra declined flags if I can help make the spam filter smarter and more effective}

Answer 1

Spam vs Excessive Self-Promotion

According to What is the exact definition of "spam" for Stack Overflow?,

Spam is an unsolicited commercial advertisement. We've all seen it, and we all know what it looks like. It looks like the same stuff you see in your spam folder when you look at your email.

Spam by this definition is handled differently from "excessive self-promotion"

Excessive promotion is a bit different than spam. Excessive promotion occurs when a user answers the question, but then puts a link to their blog or website in their answer without disclosing that they are linking to their own website. They may do this for many answers.

Reporting Spam and Excessive Promotion

Spam is treated differently from excessive promotion. When you flag posts as "Spam", and the post is deleted as such, the post then becomes part of review audits, is fed into the Stack Exchange spam detector, and the spamming account is heavily penalized with -100 reputation.

People who are merely excessively promoting themselves without full disclosure are given warnings by moderators, who may edit out the promotional links from the user's posts. When you see someone who appears to be improperly promoting themselves, flag their posts with "Other" and explain that the excessive promotion (providing multiple links helps the moderators out).

This Particular Case

In this particular case, the user's post is not an obvious commercial advertisement, along the lines of

Buy Viagra, will make you last longer in bed!

The question was about "Integrating vimeo videos in ios app", and the linked video is about "Vimeo Video Player For ios 7 (Vimeo Integration Ios)", which apparently has Xcode integration (or whatever), but it's not an explicit commercial advertisement...it even appears to be somewhat relevant to the question. Additionally, there's no obvious evidence that the OP is affiliated with the product.

The OP could just be someone who's unaffiliated, and a spam flag would pose extremely harsh penalties on his account. Flagging using "Other" and explanation the apparent excessive promotion would be the right call in this case.