As a general rule, no.
The FBI shouldn't have used flimsy, unverified accounts or omissions of facts to continue it's justification to survey Carter Page. However, on the whole Carter Page wasn't the only person they kept a watchful eye on and, thus, he wasn't the only person whom it utilized (a) human source(s) to obtain information on as far as reporting on Page's movements, conduct or associations. He just comes off as the primary asset because it was through him that the FBI was able to justify its continuance of procuring FISA warrants.
Is it reasonable (and, thus logical) to assume that had the FBI been honest about Carter Page concurrently working with another US intelligence agency they wouldn't have pursued a FISA warrant at all? YES, ABSOLUTELY! Because it's highly unlikely the FBI would have consider him a foreign agent of Russia. Therefore, if we are to assume that Carter Page was the only asset the FBI had to monitor in order to learn what the Trump campaign was up to, then yes, I would totally agree that the entire Russia investigation was a scam from the very beginning. But Carter Page wasn't the FBI's only asset; there were others. Carter Page was simply the easiest asset to survey because of his constant travels between the U.S. and Russia and his involvement with the Trump campaign (limited though it was).
Thanks for your response a well balanced and thought out discussion!
With that being said to continue on you have brought up specifics that need to be addressed as well.
You are CORRECT there was others that were pursued by the FBI, but currently on the books we only know of the FISA of carter page. The other sources at this time did NOT have an active FISA on them
This is a significant difference. What I mean is.
1) using CHS as a legal means is a common element. But this LIMITS the specific scope of the CHS's ability to interact.
2) THE FISA is a tool that is able to collect data on the target and any specific time.
3) THE CHS is limited in collection of direct data and communication
4) The FISA has indirect collection as they are able to monitor all contact by the target. AGAIN if Carter page managed to call Trump. The FISA may have the ability to collect this Phone call and record. While Trump would needed to be masked in the disclosure they HAVE IT. Only if in a criminal action could it be revealed. THIS IS HIGHLY intrusive to a NON criminal. During the Period of Carter page's active FISA data was collected the whole time.
OK so.... that fact that is concerning, They could have used a CHS on Page and NOT a FISA, but they targeted Page, they omitted exculpatory evidence to push the application through. WHY was Page such the heavy target, or..... was page NOT the actual target... the indirect collection of data by using page as the conduit was the ACTUAL reason........ A low level person that wasnt even charged with a crime. The better person IF anything would have been MANAFORT, they should have put a FISA on HIM.... But he would be TOO high level and TOO suspicious no?
Anyways again, You highlight that there were additional sources and I can concede, but the issue is the FISA was only used on Page why? And more so it was altered to push through.
NOW The Predicate to initiate investigations is one but to continue and maintain an investigation with omitted exculpatory evidence is the BIGGEST ISSUE. And even bigger issue. THAT is whats being over looked in my opinion and dusted under the rug