1. Keith Curle has declared himself "choosy" with the money he insists is at his disposal, but the lack of impact signings since the turn of the year has surely held United back.
January brought the welcome permanent addition of Mark Ellis, the extension of Hallam Hope's loan and then the temporary arrival of Brandon Comley, now injured.
But there was understandable frustration as deadline day was accompanied by tumbleweed (apart from the opinion-splitting departure of Gary Dicker to Kilmarnock), while nothing has come through the loan window since.
United's boss maintains he will not waste the club's money on players he does not instinctively believe will improve his squad.
Nothing wrong with that principle. But Carlisle's struggle to locate a catalyst or two has left them short of inspiration in these current tight games.
Their results right now reflect a lack of fresh quality in a couple of areas, and time is running out to find it.
One argument at play among some fans - denied by Curle - is that the manager is in fact keeping his powder dry until the summer, when he may be able to build a better side for the long-term.
2. This season began with a glut of goals but things have become notably more meagre recently.
Goalscoring is a matter for the team, not just the centre-forwards, but it cannot be denied that Carlisle's strikers are not at their most deadly right now.
Jabo Ibehre, after starting the season magnificently with 14 goals from 20, has scored once in his last 14 outings.
Charlie Wyke is on double figures for the campaign but just two of his goals have come in his last 14 appearances.
Derek Asamoah has one from 19, Hallam Hope (albeit often used wide) two in 13, and Steven Rigg is only just feeling his way back in after injury.
Recent missed chances have cost Carlisle up front, and there is also a lack of consistent goal threat from central midfield, where Jason Kennedy's return of one league goal is disappointing, and Luke Joyce (none) was not signed for his shooting.
Bastien Hery is in and out of the side, awaiting his first United goal. Angelo Balanta has been told to work harder if he is even to make the squad. Joe Thompson is a wide player waiting for more chances.
It might be that United are missing another midfielder with goalscoring potential, Antony Sweeney, more than they realise.
But overall this is a dry period that is threatening to end a promising season early. A couple of healthy victories, with goals aplenty, are sorely needed to send confidence flowing back through Curle's finishers.
3. A common query among fans concerns United's style of play, which has grown strikingly more direct since winter fell.
The sometimes risky but also attractive passing game unveiled in late summer is barely seen today.
Instead, Carlisle are much more eager to get the ball up to their big strikers early, whilst also relying on long throws.
The quality of mid-season pitches was used as one explanation for this by Curle some time ago. But with spring at hand, one wonders if the manager will ever restore his confidence in United's previous way of playing.
In general Carlisle are not as leaky at the back these days, with Ellis' arrival among the reasons for this.
Is it not, though, possible to retain this strength but also be a little easier on the eye, and more progressive in how you work your way up the pitch?
Or maybe Curle has simply conceded that his squad lacks ball-playing flair in certain areas and it is a matter of personnel, not strategy, that has forced his tactical hand in a traditionally robust division.
4. The floods, and Carlisle's FA Cup run, were two monumental distractions and United's dip in form can arguably be traced to both.
The effect of having their stadium and facilities ruined by Storm Desmond cannot be underestimated. There was a great coping spirit around Cumbria in December and United certainly tapped into that themselves.
But the floods left lots of people facing many hard and draining months, and there may be something in the daily struggle that has also left United weary.
As well, Curle's side poured so much into an exhausting cup run, which delivered the bounty of a sell-out home tie against Everton, that perhaps they have found it harder than they expected to refill their tank.
They ended 2015 with three league wins from four, and also a draw at high-flying Oxford that could easily have been another triumph. This year it is three league wins from 12, the latest result a sterile 0-0 draw at bottom side Dagenham.
It has led to a creeping frustration among fans which became quite vocal at times on Tuesday night. It would be wrong, and an excuse too far, to say this team is on its knees after a hard campaign.
But they do look in need of some fresh life. There is still nearly a quarter of the league campaign to go and United must find a way of renewing their energy for some potentially huge games ahead.
5. League Two is so unpredictable - and, some argue, so modest in quality - that you can assemble form like Carlisle's and still be one win shy of the play-offs.
They are two points south of the top seven and only the defeatist would write off a side at this stage.
Yes, United have made life harder for themselves than necessary, since they and the rest of the chasing pack are probably now fighting over one place (seventh, currently held by AFC Wimbledon).
But it is right to look for reasons to be optimistic, even in the wake of Tuesday's blank in east London.
Most of Curle's players are now fit and available, with Sweeney the only remaining absentee. Danny Grainger, out since January, now has two games in his legs and the skipper should soon return to full flow.
Tom Miller's availability is another bonus, while David Atkinson can also be expected quickly to rediscover consistent defensive form after his own injury.
These players, and the rest currently stuttering, were responsible for building an impressive rumble of form in late 2015.
When Carlisle cuffed aside an admittedly ordinary Notts County at Deepdale on December 19, going fifth, it seemed anything was possible.
It could still be, and wouldn't require an enormous upturn. But each frustrating 90 minutes that passes represents another chance lost.
At some stage soon the victory that restores some of that old swagger simply needs to come.
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